bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECT OF MANURE AND P FERTILIZER ON PROPERTIES OF A BLACK CHERNOZEM IN SOUTHERN SASKATCHEWAN
Authors: CAMPBELL C. A. , BIEDERBECK V. O. , SELLES F. , SCHNITZER M. , STEWART J. W. B.
Published: March 2010

The effects of application of manure and P fertilizer on wheat yields in a fallow-wheat-wheat rotation on a Black Rego Chernozemic clay soil have been studied for 36 yr. The objective of this study was to identify the effects of manure on soil characteristics that could be related to the reported progressive yield increases over time and an apparent improvement in soil tilth. Soil samples were taken in 1982 from the check (no treatment), and from treatments receiving 13.4, 20.2 and 26.9 t ha−1 of manure applied each fallow year, and 112 kg ha−1 of seed-placed 11-48-0 applied to wheat after summerfallow. Soil physical and P-related parameters were determined for depth increments to 30 cm; the total-N and 15N data to 90 cm; other data were for the 0- to 7.5-cm depth. Manure had no effect on bulk density or hydraulic conductivity. However, it increased the total C and humic acid (HA) content of the soil, the percent of soil C as HA-C, the C concentration in humin, and the percent of total soil N as humin-N. Manure significantly increased the percent of HA-N but not humin-N present as amino acid and amino sugar-N, but increased amino acids and the amino sugars in the humin hydrolysate. The net rate of N mineralization and the available forms of inorganic P were all increased significantly by manure. The natural 15N-abundance technique showed that a significant though small proportion of soil N was derived from manure. Manure had no effect on soil microbial biomass C and N, soil respiration, and the quantity of potentially mineralizable N. Applied P had no effect on N-related parameters measured; its effect on available P was not measured. It was concluded that manure increased crop yields by improving the N- and P-supplying power of the soil, and improving the physical environment of the soil through its effects on the humic colloids. Key words: Humic substances, soil P fractions, soil biological properties, natural 15N abundance, net N mineralization
L’EFFET DE L’INCORPORATION DE MATIERES LIGNEUSES SUR L’EVOLUTION DES PROPRIETES CHIMIQUES DU SOL ET SUR LA CROISSANCE DES PLANTES
Authors: NDAYEGAMIYE ADRIEN , DUBÉ ARMAND
Published: March 2010

Bark and pig manure were incorporated in soil every 2 yr from 1982 to study their effects on cereal and forage yields and on soil chemical properties. Bark incorporation induced an intense nitrogen immobilization in soil. Consequently yields and nitrogen uptakes by plants were very low in 1982 on bark treatments, but significantly higher in the following years (1983–1985), more especially when bark and pig manure were applied together. Nitrogen immobilization was less intense at the second bark application. Plants may therefore absorb the remineralized soil nitrogen from the early fixed nitrogen during the initial bark decomposition. Soil analysis showed an increase of C:N ratios mainly in bark-amended soils. These C:N ratios ranged from 19 to 21 for control and bark treatments, respectively. In the course of 4 yr, the organic matter content on the < 2 mm fraction increased very slowly, although significantly at P = 0.05 where bark and pig manure were applied together. However, no cation exchange capacity change in soil has yet been observed. In the short term, bark alone decomposed very slowly in soil, and nitrogen immobilization effects still persist. Pig manure applied with bark increased its decomposition and humification, characterized by low optical ratios (E4:E6) of 5.4 to 5.0 compared to control and bark treatments with E4:E6 > 6. Bark application to soil, together with pig manure as nitrogen source, may improve long-term soil productivity. Key words: Bark, organic matter, decomposition, humification, immobilization, CEC
EFFECT OF IRRIGATION AND NITROGEN, PHOSPHORUS AND POTASSIUM RATE AND PLACEMENT ON TOMATO FRUIT YIELD AND SIZE
Authors: BLATT C. R. , McRAE K. B.
Published: March 2010

Tomato (Lycopersicon esculentum Mill. ’Cabot’) was grown in Atlantic Canada on two soil types that contained either "high" (350–500 kg ha−1) or "low" (85–150 kg ha−1) soil P (Bray no 2). Application of water by trickle irrigation increased total (ripe + green fruit) marketable yields in 3 of 4 yr. Since there were no irrigation versus NPK fertilizer treatment interactions, all treatments were irrigated in subsequent experiments. On the "high" P soil, maximum yield was attained with side-banding P at 8.7 kg ha−1 at transplanting with preplant broadcast N and K. At the same broadcast N and K rates, it required 35 kg ha−1 of broadcast P to achieve the same yield. Similarly, on the "low" P soil with the same rates of N and K broadcast, banding P at rates up to 17.5 kg ha−1 was approximately four times as efficient as either banding or broadcasting all three nutrients in terms of increasing yield. Maximum ripe and total fruit yields, respectively, for the all-banded and all-broadcast methods (80 kg N, 70 kg P and 66 kg K ha−1) were 24 and 17% less than attained when P was banded at 35 kg ha−1 with the same rates of broadcast N and K. Doubling the N and K rates with P increased to 70 kg ha−1 further increased yields by 28% for the P-banded plus N and K broadcast method. However, these high N and K rates seriously depressed yields for the all-banded application. Banding P with broadcast N and K also produced larger fruit than either of the other two application methods. Results clearly demonstrated the yield advantage of irrigation and the superiority of side-banding P with broadcast N and K over banding or broadcasting all three nutrients for maximizing yields and fertilizer-use efficiency for tomato production in the Atlantic Region of Canada. Key words: Tomato, broadcast, banding, phosphorus efficiency, irrigation
THE EFFECT OF ORCHARD SOIL MANAGEMENT ON SOIL TEMPERATURE AND APPLE TREE NUTRITION
Authors: NEILSEN G. H. , HOGUE E. J. , DROUGHT B. G.
Published: March 2010

Soil temperature was measured from 1981 to 1985 at 0.2- and 1.0-m depths for four soil management treatments which included full ground cover, total vegetation control, shallow tillage and black plastic mulching in a high-density orchard planted to Bisbee Red Delicious (Malus domestica Borkh.) on Mailing 26 rootstock. Ground cover suppression treatments, especially black plastic mulching, increased degree day accumulations above 10 °C in all 5 yr at 0.2-m and in 3 yr at 1.0-m depths relative to full ground cover. However, these treatments also resulted in more extreme temperature fluctuations as characterized by higher summer maximum and lower winter minimum temperatures under black plastic mulching. Despite a potential for more extreme soil temperatures, apple yield was significantly higher under black plastic relative to full ground cover. For these two contrasting temperature treatments, leaf N and Mg concentrations were usually significantly higher under black plastic while leaf P and K were consistently higher and leaf Ca and Zn were occasionally higher under full ground cover. Most of these differences were, with the possible exception of leaf Zn, attributed to the competition for, or recycling of, nutrients by orchard floor vegetation. Mean monthly soil temperatures at the two depths under the four soil management treatments could be predicted by simple linear regression techniques from soil temperature measurements at the Summerland Research Station Meteorological Recording Site. Key words: Bisbee Delicious apples, degree days, ground cover, suppression, black plastic mulching, leaf nutrition
SOIL REDISTRIBUTION ON THREE CULTIVATED NEW BRUNSWICK HILLSLOPES CALCULATED FROM 137Cs MEASUREMENTS, SOLUM DATA AND THE USLE
Authors: JONG E. DE , WANG C. , REES H. W.
Published: March 2010

137Cs, solum data and the USLE were used to estimate soil erosion on three medium-textured soils in New Brunswick that had been in nearly continuous potato monoculture over the past 15 yr. Sampling transects were located on slopes ranging from 425 to 1040 m long, and from 4.8 to 6.0% slope. Ten equally spaced sites were sampled on each transect. The 137Cs data were used to divide the sampling sites into four groups: deposition, little erosion or deposition, moderately eroded and severely eroded areas. The four groups generally agreed well with soil profile properties. Solum, A horizon thickness and organic carbon content of the A horizon all decreased going from depositional sites to sites with severe erosion. Variations in A horizon thickness and organic carbon content explained about 65% of the variation in 137Cs. Soil losses predicted by the USLE were better correlated with soil losses calculated from 137Cs when the 137Cs data were used to delineate slope segments that were subject to erosion than when 137Cs and USLE soil losses were calculated on a field basis. The USLE overestimated soil losses at high erosion rates. Key words: Erosion, deposition, 137Cs, USLE, soil profile
RELATIONS ENTRE LA TENEUR EN MATIÈRE ORGANIQUE ET LA MASSE VOLUMIQUE APPARENTE DU SOL
Authors: ANGERS D. A. , SIMARD R. R.
Published: March 2010

As a part of a study on soil compaction, measurements of soil bulk density were taken three times during the season at five sites and three depths. Strong negative correlations were obtained between soil organic matter content and (1) soil bulk density and, (2) the increase in bulk density during the season. Key words: Bulk density, compaction, organic matter
EFFECT OF TYPE, RATE AND INCORPORATION OF LIME AND OF NITROGEN FERTILIZER AND GYPSUM ON MOVEMENT OF LIME IN SOIL COLUMNS
Authors: HOYT P. B. , DROUGHT B. G. , NEILSEN G. H. , HOGUE E.
Published: March 2010

Soil columns were used to study downward movement of calcite and dolomite applied at two rates on the soil surface or incorporated 0–5 cm deep in combinations with gypsum and surface-applied N fertilizer. The columns were irrigated with 800 mm of deionized water applied over 3 wk. Incorporation of the liming materials greatly accelerated their downward movement in soil. Calcite and dolomite were equally effective in raising soil pH at the lower depths. Neither gypsum nor fertilizer nor doubling the liming rate had much effect on lime movement. Key words: Lime movement, calcite, dolomite, gypsum
RELATION DU POTASSIUM EXTRAIT PAR EUF ET QUELQUES MÉTHODES CHIMIQUES AVEC LES PROPRIÉTÉS DU SOL ET LE RENDEMENT DES PLANTES
Authors: TRAN T. SEN , TABI M. , KIMPE C. R. DE
Published: March 2010

The objectives of this study were to compare the EUF procedures (50, 200 and 400 V) and some chemical methods (1 N NH4OAc, 0.01 M CaCl2, 1 N HNO3) in order to estimate the K fertility levels of 60 Quebec soils. The EUF-50 V-K quantities corresponded to CaCl2-K while EUF-(50 + 200 + 400 V) to acetate-K. The relations between EUF-(50 V)-K, EUF-(200 V)-K to Acetate-K were improved when introducing clay contents, CEC values and K saturation levels. On the other hand, soil pH, carbonate and exchangeable (Ca+Mg) contents had significant effects on the relations between EUF-400 V-K and Acetate-K. A greenhouse experiment, using ryegrass as the test plant, was carried out on these soils with two treatments (complete fertilization with and without K). EUF-400 V-K, Acetate-K and EUF-(50 + 200 + 400 V)-K were the best criteria to estimate relative yields and K uptake by the plant. EUF-(50 + 200 V) underestimates K fertility level for soils rich in clay, having high pH (H2O) or exchangeable (Ca+Mg) contents. Higher correlation coefficients for K uptake by the plant were obtained in multiple regression where EUF-(50 + 200 V)-K and EUF-400 V-K were taken into account. The relation between plant K uptake and K values determined by all methods were improved by considering the K saturation levels on cation exchange sites. Acetate-K contents explained up to 88% of the variation in K uptake when K saturation level was introduced. Finally, this method can overestimate the K fertility levels for soils rich in clay or organic matter. Key words: Electro-ultrafiltration, available K, soil properties, exchangeable K
THE SEASONAL VARIATION OF SOIL EROSION BY WATER IN SOUTHWESTERN QUEBEC
Authors: KIRBY P. C. , MEHUYS G. R.
Published: March 2010

Fallow plots were maintained at four sites that varied with respect to soil type and slope aspect and gradient to determine seasonal patterns of soil loss in southwestern Quebec. Equipment used to measure and record runoff included tipping-bucket flowmeters and Datapod digital recorders. Soil loss was measured on a seasonal basis from September 1983 to August 1985, to compare the percentage of annual soil loss by water that occurred during winter and summer months. Summer soil loss accounted for approximately 80% of the total annual soil loss from coarse-textured sites. Winter soil losses at the fine-textured site were responsible for almost 90% of the annual soil loss from that site. Key words: Soil erosion, universal soil loss equation, spring runoff
MINERALOGICAL VARIABILITY OF THE CLAY IN A MAP DELINEATION OF BRANDON SOIL
Authors: ROSS G. J. , WANG C. , HILL R. G.
Published: March 2010

The mineralogical variability of the clays from the Ap and BCg horizons of 20 pedons in a delineation of Brandon soil near Ottawa was measured. The soil has level topography, is dominantly poorly drained, and has developed from marine clay during the past 8000 yr. Smectite, vermiculite and mica were the dominant clay minerals, whereas quartz, feldspars and amphiboles were generally present in smaller amounts. The coefficients of variation (CV) among pedons were generally less than 20% indicating that the lateral distribution of minerals in the clay was relatively uniform. This was supported by the low variability (CV of 10% or less) of the chemical properties of the clay, such as cation exchange capacities and K contents, which are generally related to clay mineralogy. There were more significant differences in clay mineralogy between Ap and BCg horizons. Differences appear to have resulted from pedogenic weathering. The clay from the Ap horizon contained a higher proportion of smectite and lower proportions of mica, albite and amphiboles. Presumably, some mica had expanded to form smectite and some primary mineral grains had weathered. Decreased total amounts of Na, K and Ca in the Ap clay also reflected this weathering. The lateral uniformity of the clay mineralogy was accounted for by the relatively uniform soil forming factors and processes in this map unit. The confidence limits for variations from means of mineral contents in replicated clays as well as other results indicate that the determination of spatial variability of clay mineralogy is limited by the precision of analytical methods for mineral quantification. Key words: Mineralogical variability, map delineation, Brandon soil
THE ZINC FERTILITY OF SASKATCHEWAN SOILS
Authors: SINGH J. P. , STEWART J. W. B. , KARAMANOS R. E.
Published: March 2010

Current criteria for predicting zinc (Zn) deficiency in Saskatchewan soils are based on DTPA-extractable Zn values. DTPA-extractable Zn levels in 12% of 1200 samples taken across Saskatchewan contained less than 0.5 mg Zn kg−1 soil and would be classified as potentially Zn deficient. However, 23 field trials in 1982, 1983 and 1984 with spring wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), lentils (Lens esculenta Moench.), peas (Pisum sativum L.), alfalfa (Medicago sativa L.), corn (Zea mays L.) and flax (Linum usitatissimum L.) produced only one significant response to Zn fertilization. No yield benefits due to either annual or residual application of Zn fertilizer were obtained even on high lime soils or those containing DTPA-extractable Zn levels below 0.5 mg kg−1 soil. Hence, current soil criteria to identify Zn deficiencies under the prevailing cropping systems must be revised to reflect these findings. Key words: DTPA-extractable Zn, crop response, critical level
COMPARISON OF 13C CPMAS NMR AND CHEMICAL TECHNIQUES FOR MEASURING THE DEGREE OF DECOMPOSITION IN VIRGIN AND CULTIVATED PEAT PROFILES
Authors: PRESTON C.M. , SHIPITALO S.-E. , DUDLEY R. L. , FYFE C. A. , MATHUR S. P. , LEVESQUE M.
Published: March 2010

Solid-state 13C CPMAS NMR was used to examine organic soils from virgin, 5-yr and 15-yr cultivated sites. In agreement with previous studies using other techniques, the chemical effects of cultivation were essentially confined to the plough layer. Cultivated sites had less carbohydrate, and increased lipid and methoxyl carbon; these changes were similar to those found with depth, due to natural decomposition. Changes in aromatic and phenolic carbon with depth or years of cultivation were small. When the NMR data were compared with other indicators of decomposition, there were no correlations between the pyrophosphate index and NMR parameters. Rubbed fiber correlated positively with carbohydrate, and negatively with lipid. This study supports the use of rubbed fiber as a routine indicator of the degree of decomposition, and the use of 13C CPMAS NMR for elucidating chemical changes in organic soils. It also illustrates the need to separate more clearly chemical changes occurring during decomposition or cultivation, from purely physical changes due to drying, compaction, and particle size diminution. Key words: 13C NMR, degree of composition, peat profile, organic soils
COMPARISON OF MEASURED SOIL 137-CESIUM LOSSES AND EROSION RATES
Authors: KACHANOSKI R. G.
Published: March 2010

Atmospheric deposition rates of 90Sr and analysis of soil samples from non-eroded sites indicated base levels of total soil 137Cs were approximately 2700 Bq m−2 in southern Ontario in 1985. Measured 137Cs losses (1965–1976) from long-term runoff plots were significantly correlated to measured soil losses during the same period. Monitoring temporal changes in soil 137Cs should be an accurate method of estimating soil loss in southern Ontario. Key words: Soil loss, 137Cs, Ontario, runoff plots
TOLERANCE OF BRUSSELS SPROUTS TO HIGH BORON LEVELS
Authors: GUPTA UMESH C. , CUTCLIFFE J. A. , CORMIER RENALD
Published: March 2010

Boron application rates as high as 8 and 16 kg ha−1 were not toxic to Brussels sprouts (Brassica oleracea L. ssp. gemmifera). These rates resulted in leaf tissue B levels of 123 and 161 μg g−1 and of 7.6 and 9.1 μg HWS B g−1 soil, respectively. Rates of 8–16 kg B ha−1 would, however, be seriously toxic to many crops. It is therefore strongly recommended that rates of B applied to Brussels sprouts should not exceed 2 kg ha−1. Such B applications should eliminate B deficiency in most crops and would not pose a threat of B toxicity to crops grown in the following year. Key words: Eastern Canada, Brussels sprouts yields, field studies, boron
DESALINIZATION OF AN IRRIGATED, MOLE-DRAINED, SALINE CLAY LOAM SOIL
Authors: SOMMERFELDT T. G. , CHANG C.
Published: March 2010

Desalinization of an irrigated, saline, clay loam soil that had been drained with unlined and lined mole drains, at 0.7 m depth, was determined during a 10-yr reclamation period. Within 5 yr the mean electrical conductivity (EC) of the surface 60 cm of soil, for about one-half of the plot area, had been reduced from greater than 8 to less than 4 dS m−1. The mean EC for the plot area at the 0- to 60-cm and 0- to 180-cm depths declined in a logarithmic order with time. Desalinization of the surface 30 cm of soil was greater under the unlined drain regime than under the lined, but at 30- to 120-cm depths, desalinization was greater under the lined. The salts were mostly sodium, calcium and magnesium sulfates. Although the unlined mole drains had an average discharge of 24% of that from the lined, the average salt discharged through the unlined drains was 80% of that from the lined ones. The lined drains removed more salts over a greater range of depths. Key words: Desalinization, reclamation, mole drainage, soil salinity
DISTRIBUTION OF N IN A SIMULATED PROFILE OF A PODSOLIC GRAY LUVISOL FOLLOWING UREA FERTILIZATION
Authors: BAKER J.
Published: March 2010

A laboratory leaching study, using simulated profiles, was undertaken to help explain the ability of a Podsolic Gray Luvisol to retain a considerable portion of the added urea-N in the surface 61 cm of its profile. A Podsolic Gray Luvisol, supporting lodgepole pine, in the Alberta foothills was sampled by horizons. Reconstructed profile columns were used in a laboratory leaching study to determine the effect of urea fertilization on the movement and distribution of N. Leachates were collected periodically and analyzed for total N. Upon termination of the leaching phase, soil N was fractionated by acid (0.1 M HCl) and alkali (2% NaOH) extractions. Volatilization loss of N approximated 18.5% of that retained by the fertilized columns. The addition of urea did not significantly increase the N in the leachates. Added fertilizer was retained mainly in the surface (L-F, Ah, Ae and Bf) layers of the reconstituted profiles. The largest portion of this retained N was HCl extractable. However, in the lower layers of the fertilized profiles most of the retained N was recovered in the humic fraction. It is postulated that added N as well as residual soil N mobilized by the urea treatment are retained in the soil by reaction with metal ions, hydrous oxides of Fe and Al and expanding clays. Key words: Gray Luvisols, urea, forest fertilization, N fractionation
UTILIZATION OF CATTLE MANURE CONTAINING WOOD SHAVINGS: EFFECT ON SOIL AND CROP
Authors: SOMMERFELDT T. G. , MACKAY D. C.
Published: March 2010

A 7-yr study was conducted to determine the effects of repeated annual applications of manure containing softwood shavings (M + S) at 50 t ha−1 on the soil and its productivity, relative to manure without shavings (M) at 50 t ha−1 and nitrogen fertilizer (F) at 67 kg ha−1. The EC, OM, total N and C:N ratio of the soil of the M + S and M + S + F plots to 60-cm depth were not significantly greater than those from the M plots, and in some instances they were significantly less. The NO3-N and total N and available P contents of the soil from the M + S treatment were significantly lower than those from the M treatment. Immobilization of N in the M + S and M + S + F treatments was indicated. Barley (Hordeum vulgare L. 'Gait') straw and grain yields and protein content of the grain were generally greater under the M than under the M + S treatment. When N fertilizer was included in the M + S treatment (M + S + F) the yields were similar to those of M, and the protein content increased. If manure with shavings is used for fertilizer, supplemental N should be applied to offset N immobilization. Key words: Manure disposal, manure, manure with wood shavings, nitrogen, crop yields
ACCUMULATION OF NATIVE ARSENIC IN ACID SULPHATE SOILS IN ALBERTA
Authors: DUDAS M. J.
Published: March 2010

Acid sulphate soils belonging to the Boundary and Josephine soil series were analyzed for As to determine mineral partitioning, form, and redistribution of the element. Samples of soil, natrojarosite, and zones enriched in iron oxides were collected from upper and lower slope positions. Levels in bulk samples were 10 times higher and levels in some Fe oxides were 100 times higher than normal background abundances. Arsenic was partitioned into silt and clay fractions and appeared related to the distribution of iron oxides in the size separates. Most of the translocated As accumulated in the vein-like network of segregated iron oxide in fractures extending downward from B horizons. These vein samples contained as much as 450 mg As kg−1, primarily as adsorbed As associated with both crystalline and amorphous forms of iron. Microbiologically mediated losses of As had depleted surface horizons of the element. The weathering of pyrite is believed to account for the accumulations of As in acid sulphate soils. Key words: Arsenic, acid sulphate soil, iron oxyhydroxides, trace elements
EFFECTS OF THREE SOIL CONDITIONERS ON WATER CONTENTS IN TWO SOILS AT THREE PRESSURE-PLATE MATRIC POTENTIALS
Authors: STEVENSON D. S.
Published: March 2010

Soil water contents of a sandy loam and a silt loam soil were measured at −1500, −100, and either −20 or −30 kPa (the finer texture at −30 kPa) on pressure plate equipment, after samples of each soil had been treated with one of three soil conditioners or with water as a control treatment. One of the soil conditioners increased the soil water retention of both soils at all matric potentials while the other two increased soil water retention at −1500 kPa in the silt loam. The implications in terms of water availability to plants are discussed briefly. Key words: Matric potentials, soil water retention, soil conditioners, laboratory
DEGRADATION OF MELANOIDINS BY SOIL MICROORGANISMS UNDER LABORATORY CONDITIONS
Authors: IVARSON KARL C. , BENZING-PURDIE LAURE M.
Published: March 2010

Synthetic melanoidins, unlabeled and U–14C labeled, mixed with sand, inoculated with a soil suspension and incubated in Warburg vessels for 30 d, decomposed slowly. Reactants (amino acids, sugars and NH4 salts) involved in melanoidin formation had no influence on rate of degradation, nor did the pH at which the melanoidins were synthesized. However, temperature of synthesis affected the rate; an increase led to a decrease in biodegradability paralleled by both increase in C:N ratio and unsaturation. At lower temperatures species of Penicillium, Cladosporium and Paecilomyces were the dominant fungi degrading the polymers, while at higher temperatures only Penicillium species were present. Key words: Melanoidins, decomposition by soil microbes
COMPARISON OF MORPHOLOGY AND POROSITY OF A SOIL UNDER CONVENTIONAL AND ZERO TILLAGE
Authors: SHIPITALO M. J. , PROTZ R.
Published: March 2010

Effects of tillage on soil morphology and porosity were investigated in plots planted to corn (Zea mays L.) for seven consecutive years. Micromorphometric analyses indicated that Ap horizons of no-till plots had approximately half the macroporosity (pores ≥ 200 μm equivalent circular diameter) of those of conventionally tilled plots. Loss of macroporosity was characterized by a decrease in mean pore size and a tendency for pores to become elongated, less tortuous, and oriented parallel to the soil surface. Obvious zoological activity, which consisted mainly of burrowing earthworms, resulted in two to nine times more bioporosity in a no-till pedon than in a conventionally tilled pedon. Earthworm activity also contributed to the formation of 5-cm-thick B & A horizon and a more uniform distribution of organic carbon than in the conventionally tilled pedon. These differences in morphology are reflected in the classification under Soil Taxonomy but not under the Canadian System. We speculate that zoological activity may serve to counteract the reduction in macroporosity in the Ap of the no-till pedon. Key words: Bioporosity, earthworms, micromorphometric analysis, zoological activity
PHYSICAL PROPERTIES OF SOME PRINCE EDWARD ISLAND SOILS IN RELATION TO THEIR TILLAGE REQUIREMENT AND SUITABILITY FOR DIRECT DRILLING
Authors: CARTER M. R.
Published: March 2010

Successful reduced tillage systems depend on suitable soil types and the maintenance of optimum soil structure. Studies were conducted to assess the tillage requirement of some well-drained Podzolic and Luvisolic soils in Prince Edward Island and their suitability for direct drilling. Relatively high amounts of silt and fine sand indicated that the soils were structurally unstable with a propensity for compaction. Compactability was inversely related (r2 = 0.90) to concentrations of soil organic carbon over a range of 0.2–2.0%. In the Ap horizons, where organic carbon exceeded 1.6%, the level of macroporosity (equivalent pore diam. > 50 μm) was generally greater than 10%. The B horizon and lower level of the Ap horizon, generally, had low porosity and organic matter, although pore continuity was adequate. Macroporosity was closely related to soil bulk density (r2 = 0.81). Penetrometer resistance down the soil profile indicated a relatively shallow rooting depth potential of 25–40 cm. A 3-yr direct drilling study with spring cereals illustrated that some degree of soil loosening is required to maintain optimum soil structure. Soil limitations for direct drilling were mainly low resistance to compaction combined with low potential for regeneration of soil structure. The possible implications of the soil physical properties are discussed in relation to the use of direct drilling within the short-term rotational mixed farming systems of Prince Edward Island. Key words: Soil structure, macropores, Podzolic soils, Luvisolic soils
INFLUENCE OF CROPPING TREATMENTS ON THE MONOSACCHARIDE CONTENT OF THE HYDROLYSATES OF A SOIL AND ITS AGGREGATE FRACTIONS
Authors: BALDOCK J. A. , KAY B. D. , SCHNITZER M.
Published: March 2010

The influence of three cropping treatments on the quantitative and qualitative composition of the carbohydrate fraction of a silt loam soil and its water-stable aggregates was assessed. Three cropping treatments were considered: bromegrass (Bromus inermis Leyss.) grown continuously for 15 yr (B15), grain-corn (Zea mays L.) grown continuously using conventional tillage for 15 yr (C15), and grain-corn grown continuously for 13 yr followed by 2 yr of bromegrass (B13C2). Six water-stable aggregate size fractions ranging from 8.00–4.70 to 0.25–0.10 mm in diameter were separated from the soil by wet sieving. The carbohydrate fraction was extracted by acid hydrolysis, reduced, acetylated to alditol acetates and analyzed by temperature-programmed capillary gas chromatography. Total carbohydrate content was not significantly influenced by cropping treatment but was observed to increase as aggregate size decreased irrespective of cropping treatment. The carbohydrate content in the different aggregate size fractions was positively correlated with both organic carbon and clay contents. With the exception of xylose and mannose, the monomeric sugars behaved similarly to total carbohydrates. Based on the magnitude of the ratio of the content of mannose to that of arabinose plus xylose, the contribution of plant carbohydrates to the total carbohydrate fraction increased as aggregate size decreased in the B15 treatment, but decreased in the C13B2 and C15 treatments. No significant correlations existed between either the total carbohydrate content or the content of individual sugars, and the stability of aggregates in the soils from the different cropping treatments. Key words: Wet aggregate stability, soil organic matter, soil structure, crop rotation, corn, bromegrass
LIQUID MAGNETIC SEPARATION OF IRON-BEARING MINERALS FROM SAND FRACTIONS OF SOILS
Authors: GHABRU S. K. , St. ARNAUD R. J. , MERMUT A. R.
Published: March 2010

The study provides a new liquid magnetic separation (LMS) technique for concentrating sand-sized iron-bearing minerals, in general, and for quantitative isolation of biotite, in particular, from soils. Sand fractions (100–250 μm), separated from untreated soil samples from a Gray Luvisol from Saskatchewan by ultrasonic dispersion and sieving, were processed by LMS at various levels of magnetic flux density. The LMS separates obtained at increasing level of magnetic flux density showed a decreasing iron content. A linear relationship was observed between the two variables within the range of 2.5–28.0% Fe2O3 and 0.15–0.92 Tesla (T) magnetic flux density with a correlation value of R = 0.99. Mineral grains with as low as 1.09% Fe2O3 content could be isolated from sand fractions at 1.31–1.45 T. The XRD analyses of LMS separates obtained at 0.305–0.58 T showed only biotite and its weathered products. The XRD analyses of other LMS separates showed a concentration of different solid solution series of the amphiboles, pyroxenes, garnets, tourmaline and other iron-bearing minerals in different fractions. The LMS technique is physical in nature and provides a simple, quick and effective means of isolating iron-bearing minerals from sand fractions of soils. Key words: Liquid magnetic separation, iron bearing minerals, biotite separation, sand mineralogy
QUALITY AND VALUE OF WIND-MOVABLE AGGREGATES IN CHERNOZEMIC Ap HORIZONS
Authors: DORMAAR J. F.
Published: March 2010

The 0–5 cm depth from Ap horizons of Orthic Brown, Dark Brown and Black Chernozemic soils when recently brought under cultivation, and of unfertilized Dark Brown Chernozemic soils under continuous wheat and a wheat-fallow rotation since 1912 were sampled in early May 1984. The samples were separated into 500- to 1000-μm, 250- to 500-μm, 100- to 250-μm, and < 100-μm-diameter water-stable aggregates by wet sieving. These four diameter classes of water-stable aggregates, considered to be the wind-erodible fraction of the soil, comprised 65–76% and 89–96% of the whole soil of the Ap horizons of recently and long-term cultivated soils, respectively. They were analyzed for organic matter, total N, available P, exchangeable K and monosaccharides. The source of the monosaccharides in the < 100-μm-diameter soil fraction, whether microbial or vegetative, was identified using ratios of hexoses to pentoses. The data allowed the calculation, using a number of assumptions, of the value of soil lost by wind erosion if its nutrients and organic matter had to be replaced by commercial fertilizers and cereal straw, respectively. The values obtained underscore the cost involved in poor land management, leading to wind erosion. Key words: Wind erosion, topsoil loss, organic matter (soil), monosaccharides, plant nutrients, land management
FATE OF 15N-LABELED UREA IN THE GROWTH CHAMBER AS AFFECTED BY ADDED ORGANIC MATTER AND N PLACEMENT
Authors: TOMAR J. S. , SOPER R. J.
Published: March 2010

The effects of N placement and organic matter amendments on plant uptake and immobilization of N from 15N-labeled urea were investigated in a growth chamber employing two successive crops of rapeseed (Brassica napus L.). Immature barley (Hordeum vulgare L.) (C:N ratio 20.9) and fababean (Vicia faba L.) (C:N ratio 21.8) plant residues, and sucrose were mixed throughout the soil at 10 g material kg−1 soil. Urea enriched with 20.2 atom % 15N was either mixed throughout the soil, or placed as a point in the center of the soil at 100 mg N kg−1 soil. The soil was incubated at field capacity for 30 d before the seeding of first crop and 60 d before the second crop. For the first crop of rapeseed, there was a net mineralization of N from the added barley and fababean materials regardless of N application. For total N uptake and dry matter yield of rapeseed, the mixed treatment of urea was superior to the point placement where barley and fababean residues were added. However, due to considerable biological interchange of N with added plant residues in the mixed treatment, 15N uptake was greater for the point placement of added urea (47.3 vs. 26.7%). Sucrose led to considerable net immobilization of N with the result that the point placement of N was superior to mixing for N uptake and 15N recovery. Added N remaining in the soil at harvest time after removal of the first crop's roots varied between 20.0 and 48.8% for the point placed N and between 27.5 and 79.2% for the mixed placement and was largest where sucrose was added. In spite of the large variation in 15N remaining in the soil, plant recovery of residual 15N in the second crop ranged from only 11.3 to 13.8%, except for the point placement of urea with sucrose where the value was 19.3%. Key words: N immobilization, organic residues, residual 15N, tagged urea
SOIL AND NUTRIENT LOSSES IN SURFACE RUNOFF FROM CONVENTIONAL AND NO-TILL CORN SYSTEMS
Authors: PESANT A. R. , DIONNE J. L. , GENEST J.
Published: March 2010

A natural-rainfall erosion plot study was conducted during three consecutive growing seasons (May to September) on a tile-drained sandy loam with a 9% slope to evaluate differences in soil and nutrient losses (NO3-N, P, K) from conventional (C-T) and no-till (N-T) silage corn systems. For the N-T system, corn was seeded directly into an alfalfa-timothy sod that had been treated with atrazine at 4.5 kg ha−1 a few days prior to seeding to kill the sod. The conventional system involving continuous cultivation consisted of fall moldboard plowing, spring disking with a 2.2 kg ha−1 of atrazine applied to control weeds, and seeding. When compared with the C-T system, the N-T system reduced rainfall loss as runoff by 63.6% and soil losses by 92.4%. The 3-yr total soil losses amounted to 3.87 t ha−1 for N-T and 50.68 t ha−1 for C-T. The N-T system reduced K losses by 72.6% and P losses by 93.5% with respect to C-T. NO3-N losses were significantly lower for the C-T treatment as compared to the N-T treatment. Lower percentage nutrient loss occurred in solution from C-T corn because of better incorporation of the fertilizer into the soil. Yield and percent ear were not significantly different between the two systems. Key words: No-till corn, nitrogen, phosphorus, potassium, soil erosion, surface runoff
CATALYTIC POLYMERIZATION OF HYDROQUINONE BY NONTRONITE
Authors: WANG M. C. , HUANG P. M.
Published: March 2010

The catalytic power of Ca-nontronite (0.2-2 μm) in the polymerization of hydroquinone was studied. The polymerization reaction proceeded abiotically, since there was no evidence of microbial growth in the system studied. The polymerization of hydroquinone in the presence of Ca-nontronite was substantially higher in air than in an N2 atmosphere, indicating the synergistic effect of Ca-nontronite and O2 in enhancing the reaction. After a sodium metaphosphate treatment to block the edges of Ca-nontronite, both absorbances at 472 and 664 nm of the supernatant and yield of humic macro-molecules in the Ca-nontronite-hydroquinone system were significantly decreased. However, the treatment did not eliminate the catalytic effect of Ca-nontronite. The results indicate that both Fe(III) on the edges and other Lewis acid sites of Ca-nontronite contributed to promoting the polymerization of hydroquinone. IR and ESR spectra of FA (MW > 1000) and HA (MW > 1000) formed in the supernatants of the Ca-nontronite-hydroquinone system were similar to those of natural humic substances. Key words: Catalysis, nontronite, iron(III), Lewis acid, oxygen, formation of humic macromolecules
THE EFFECTS OF ADDITIONS OF CaCO3 AND P ON THE SOIL SOLUTION CHEMISTRY OF A PODZOLIC SOIL
Authors: SIMARD R.R. , EVANS L.J. , BATES T.E.
Published: March 2010

The surface horizon from a Humo-Ferric Podzol was amended with both CaCO3, and P to investigate the changes in the ionic composition of the soil solution and the charge characteristics of the horizon. Addition of CaCO3 increased the concentrations of Ca and [Formula: see text] and decreased the total concentrations of Mg, Na, K, Al, Zn, Mn, Si and [Formula: see text] in the soil solutions. In addition, the pH of the soil solutions, the content of negatively charged sites on the soil surfaces, the relative proportion of Mn2+ and Zn2+ of sulfate ion pairs were raised. In contrast, the concentrations of exchangeable Zn and Mn, the amount of positively charged sites and the proportion of metals linked with the "modelled" fulvate ligands were reduced. The addition of increasing rates of P reduced the total concentrations of Mg, K, Al, Si, and the concentrations of [Formula: see text] and [Formula: see text] in solution but did not affect the pH or the CEC of the soils appreciably. The concentrations of Si, phosphate-P, [Formula: see text] and of the sulfate ion pairs in solution were increased by increasing P additions to the soil. Key words: Liming, phosphorus fertilization, soil solution, GEOCHEM, ion speciation
BORON AND SALINITY SURVEY OF IRRIGATION PROJECTS AND THE BORON ADSORPTION CHARACTERISTICS OF SOME SASKATCHEWAN SOILS
Authors: NICHOLAICHUK W. , LEYSHON A. J. , JAME Y. W. , CAMPBELL C. A.
Published: March 2010

In the early 1980s, an internal Agriculture Canada review, carried out as a result of a request from the Province of Saskatchewan, indicated a need to determine whether there were any sites in the Province that posed a possible B toxicity problem. The soil and irrigation water quality (SAR, pH, EC, B concentration) and the B content of alfalfa (Medicago sativa L.) were assessed at 29 irrigation projects in Saskatchewan. Langmuir and Freundlich B adsorption equations were determined for another 13 soils that allowed assessment of the effect of soil zone and texture on these relationships. It was found that, except for a few locations where crops sensitive to B may experience some problems, water quality with respect to B was acceptable for most projects. The survey showed that salinity posed more of a threat to production under irrigation than did B toxicity. Boron toxicity was closely associated with salinity problems. Freundlich equations described the data for the 13 soils best; K values ranged between 0.24 and 2.04. These values were not affected by soil zone; coarse-textured soils had K values less than 0.5 and fine-textured soils values greater than 1.5. Data presented in our study can be used to determine where the irrigation practice of individual irrigation projects in Saskatchewan is appropriate for maintaining proper salt balance in the soils so as not to impede plant growth. Key words: Boron toxicity, alfalfa, SAR, Freundlich isotherm
EFFECT OF AN ANNUAL AND A PERENNIAL CROP ON TROPHIC GROUP DYNAMICS OF NEMATODES
Authors: JUMA N. G. , MISHRA C. C.
Published: March 2010

Adult and juvenile nematode distribution and trophic group dynamics were studied in oat (Avena sativa L.) and alfalfa (Medicago sativa L.) plots of a 5-yr rotation at Breton, Alberta. Nematodes were separated into two groups: (i) adults including the late juveniles and (ii) juveniles. The adults and the late juveniles were further separated into four trophic groups: (i) plant parasites, (ii) microbivores, (iii) miscellaneous feeders and (iv) predators. Adults accounted for 83% of the total population in the oat plot and 79% in the alfalfa plot. There were no significant differences in percent distribution of adults between plots over the season or at a given date. The average density of adults over the season in the oat plot (3.3 × 106 individuals m−2) was greater than that in alfalfa plot (2.1 × 106 individuals m−2, P < 0.001). Adult density in the oat plot increased steadily from 3.2 × 106 to 4.2 × 106 individuals m−2 between July and September. There was a sharp decline after harvest. In contrast, the adult population in the alfalfa plot remained steady over the growing season. Juvenile density showed similar trends as the adults. Distribution of microbivores, plant parasites, miscellaneous feeders, and predators, was 63, 22, 13, and 2% in oat and 51, 34, 13, and 2% in alfalfa plot, respectively. Crop effect on microbivores and plant parasites was significant at P < 0.05. Our study showed that microbivores are the dominant group in cultivated soils and plant parasites build up in the presence of living roots. Key words: Microbivores, miscellaneous feeders, nematodes, plants parasites, predators, trophic groups
RESPONSE OF WINTER WHEAT TO FALL-APPLIED LARGE UREA GRANULES WITH DICYANDIAMIDE
Authors: SINGH YADVINDER , BEAUCHAMP E. G.
Published: March 2010

Three field experiments were undertaken over a 2-yr period to compare the response of winter wheat to fall-applied large urea granules containing a nitrification inhibitor (dicyandiamide, DCD) with that of commercial urea granules (prills) applied as a top dressing in the spring. The objective was to determine the effectiveness of large urea granules coupled with DCD in conserving N when applied at planting or one month after planting. Granules of 1, 2 and 3 g urea as well as 2 g urea + DCD were compared with commercial urea prills at an application rate of 80 kg N ha−1. Large urea granules, as compared with fall-incorporated commercial urea prills, were effective in conserving N over the winter period especially when applied 1 mo after planting and resulted in yields and apparent N recovery similar to those with top dressed commercial prills applied in the spring. Incorporation of DCD into 2-g granules (50 or 100 g kg−1 urea) further increased the conservation of N fertilizer as reflected by higher yields and greater apparent fertilizer N recovery. Uptake of 15N from 2-g urea granules decreased with distance from the granule. However, plants furthest from spaced large granules were able apparently to obtain sufficient N to reach the yield potential dictated by the weather and soil conditions. Yield and N recovery data indicated that N conservation increased with increasing granule size. Crop response and fertilizer N availability decreased as depth of placement exceeded 10 cm. Placement between the 5 and 10 cm depths appeared to maximize fertilizer N availability. It was concluded that a combination of large urea granules and a nitrification inhibitor (such as DCD) can effectively conserve fall-applied N and result in yield responses and N uptake by winter wheat similar to that with commercial urea prills applied as a top dressing in the spring. Key words: Time of application, yield, 15N recovery, apparent fertilizer N recovery
USE OF SOIL HORIZONS AS ECOLOGICAL SAMPLING UNITS
Authors: STRONG W. L. , ROI G. H. LA
Published: March 2010

Extractable nutrients and physical properties of Eutric Brunisols from pine and aspen stands were evaluated for their relationship to soil horizons classified according to morphological criteria. The results indicate strong horizon-nutrient associations, suggesting that soil horizons are appropriate sampling units for ecological studies concerned with below-ground nutrient and edaphic conditions. Key words: Nutrients, principal components analysis, soil horizon
AVAILABLE WATER-HOLDING CAPACITY MAPS OF ALBERTA, SASKATCHEWAN AND MANITOBA
Authors: JONG R. DE , SHIELDS J. A.
Published: March 2010

Available water-holding capacity (AWC) maps of Alberta, Saskatchewan and Manitoba were derived from Soil Landscape maps (1:1 million scale) by substituting AWC classes for soil textural classes. The maps provide information required for the geographical interpretation of soil water and crop modelling analyses. Key words: Available water-holding capacity, maps, texture
MEASUREMENT OF NEAR-SURFACE SOIL MOISTURE WITH A HYDROGENOUSLY SHIELDED NEUTRON PROBE
Authors: CHANASYK D. S. , NAETH M. A.
Published: March 2010

Numerous techniques for measuring near-surface soil moisture with a neutron probe have been reported. Placing the neutron probe horizontally on the ground surface within a hydrogenous shield has been discussed theoretically, but field adaptations have not. Such a shield was designed and used, yielding measurements of near-surface soil moisture quickly and accurately. Key words: Neutron probe, soil surface moisture, calibration
LONG-TERM EFFECTS OF AN OIL PIPELINE INSTALLATION ON SOIL PRODUCTIVITY
Authors: CULLEY J. L. B. , DOW B. K.
Published: March 2010

Crop yields and heights and soil chemical properties on and immediately adjacent to an oil pipeline right-of-way (ROW) were monitored over a 10-yr period. Effects of soil mixing on chemical properties were still apparent despite good crop management. With the exception of alfalfa, field crop yields on the ROW were reduced by an average of 28% 10 yr after installation. Key words: Soil mixing, degradation, crop heights