THE SULPHUR STATUS OF EASTERN CANADIAN PRAIRIE SOILS: THE RELATIONSHIP OF SULPHUR, NITROGEN AND ORGANIC CARBON

1985 ◽  
Vol 65 (1) ◽  
pp. 179-186 ◽  
Author(s):  
L. D. BAILEY

Surface and subsurface samples of 17 of the most agriculturally important soils of the eastern Canadian prairies were analyzed for total S, sulphate S, total N and organic C. The soils varied in texture from sandy loam to clay loam. Fifteen of the soils were of the Chernozemic order, one was Brunisolic and the other Luvisolic. The subgroups included were Orthic Blacks, Gleyed Rego Blacks, Orthic Dark Greys, Eluviated Eutric Brunisol and Orthic Luvisol. The total S of the soils decreased with depth and was significantly correlated with total N and with organic C. The sulphate sulphur extracted with 0.1 M CaCl2 accounted for an average of 2.6% of the total S in each of the three soil depths analyzed. The calculated N:S and C:N ratios averaged 8.3 and 1.25 (0–15 cm), 7.2 and 14.1 (15–30 cm), and 6.5 and 11.0 (30–60 cm), respectively. The N:S ratios, and to limited extent the C:N ratios, were used to describe the sulphur status of the soils. Soil with N:S and C:N ratios 6.0 and 12.5 (0–15 cm), 5.2 and 13.5 (15–30 cm), 4.7 and 11.4 (30–60 cm), respectively, could have a high potential to supply sulphate S to plants and may not be deficient in plant-available S. Soils with N:S and C:N ratios of 8.7 and 13.5 (0–15 cm), 7.2 and 14.7 (15–30), 6.3 and 11.2 cm (30–60 cm), respectively, may be deficient in sulphur for some crops. However, they may have a high potential to convert total S to sulphate S. Soils with N:S and C:N ratio of 12.4 and 11.2 (0–15 cm), 11.1 and 13.0 (15–30), 10.2 and 9.9 (30–60 cm), respectively, may be deficient in plant-available S and could have a low potential for conversion of total S to sulphate S. Key words: Sulphur status of soils; potential available sulphur

2012 ◽  
Vol 92 (4) ◽  
pp. 589-598 ◽  
Author(s):  
Mônica B. Benke ◽  
Tee Boon Goh ◽  
Rigas Karamanos ◽  
Newton Z. Lupwayi ◽  
Xiying Hao

Benke, M. B., Goh, T. B., Karamanos, R., Lupwayi, N. Z. and Hao, X. 2012. Retention and nitrification of injected anhydrous NH3as affected by soil pH. Can. J. Soil Sci. 92: 589–598. Anhydrous ammonia is an economical and extensively used fertilizer, yet loss after injection can reduce its agronomic efficiency. A laboratory experiment was conducted to examine how soil properties affect ammonia retention and nitrification following anhydrous NH3injection using 10 different Canadian prairie soils. Soils were also injected with atmospheric air for comparison. Following injection, soils were incubated for up to 216 h at field capacity. Among the soil properties studied [pH (1:2 water), clay, total N, and organic C contents], only pH was negatively related (R2=0.55, n=10, 24 h incubation) to percentage injected N retained by soil. The amount of N retained by soil 24 h following injection was 92±2% (mean±SEM) when pH <6, compared with 64±2% when pH>7.5. Rate of nitrification increased (P<0.001) about 48–96 h following injection and was greater in pH>7.5 than pH<6 soils. There was no difference (P>0.05) in bacterial diversity between ammonia- and air-injected soils. The slower nitrification rates suggest that potential leaching and denitrification losses in acid soils could be smaller than in alkaline soils.


2017 ◽  
Vol 10 (1) ◽  
pp. 325
Author(s):  
Hebert D. A. Abobi ◽  
Armand W. Koné ◽  
Bernard Y. Koffi ◽  
Saint Salomon F. Diahuissié ◽  
Stanislas K. Loukou ◽  
...  

Poultry litter is increasingly used as organic amendment in market gardening in Côte d’Ivoire. To know about the sustainability of this practice, its impacts on soil quality should be known. This study aimed at assessing the effect on soil fertility of composted poultry litter addition for 16 years following two distinct ways, and identifying soil parameters driving cucumber yield. Trials were laid out in a Fisher randomized block design with 3 treatments replicated 5 times each: Control (C), Surface-applied compost (SAC) and Buried compost (BC). Soil (0-20 cm) chemical characteristics and cucumber growth and yield parameters were measured. Values of all parameters were higher with compost addition compared to the control, except for the C:N ratio. SAC and BC showed similar values of organic C, total N, CEC, pH and available phosphorus. However, Ca2+, Mg2+, K+ and base saturation were higher in SAC than in BC. Relative to values in the control, the greatest changes in soil parameters were observed with exchangeable cations, followed by soil organic matter. Soil organic C and total N concentrations have doubled in SAC while Ca2+, Mg2+, and K+ increased at greater rate (702.4, 400.9 and 186.67% respectively). Also, cucumber growth parameters were the highest with compost addition compared to the control. Significant effect of the compost application way on cucumber was also observed: collar diameter, leaf area and fresh fruit yield in SAC (0.72±0.02 cm, 258.9±12.3 cm2, 11.1±1.3 t ha-1, respectively) were higher than in BC (0.56±0.01 cm, 230.2±2.5 cm2, 5.4±0.5 t ha-1 respectively). Fruit yields in SAC and BC were four times and twice higher than in the control (2.6±0.3 t ha-1), respectively. Cucumber growth parameters were determined by soil concentration in Mg2+ while yield was determined by Ca2+. Composted poultry litter should be promoted for a sustainable soil fertility management in vegetable farming systems.


2008 ◽  
Vol 54 (No. 2) ◽  
pp. 72-77 ◽  
Author(s):  
A. Kumari ◽  
K.K. Kapoor ◽  
B.S. Kundu ◽  
R. Kumari Mehta

The production of organic acids and changes during decomposition of rice straw amended with tricalcium phosphate (TCP) and Udaipur rock phosphate (URP) were studied under laboratory conditions. The organic C content of rice straw decreased and total N increased with time, resulting in a decrease in C:N ratio as the decomposition progressed. The pH decreased to acidic range in all the treatments on day 15, but became alkaline again later on. Soluble P increased at 15 days after incubation, declined later during decomposition, and was highest in the treatments containing TCP and <I>Aspergillus awamor</I>i inoculation. Citric, oxalic, formic and maleic acids were detected during decomposition of rice straw and maximum amounts were present on day 15. Citric and oxalic acids were responsible mainly for P solubilization from TCP and URP; generally, citric acid was the most effective in P solubilization.


2017 ◽  
Vol 46 (1) ◽  
pp. 26-36 ◽  
Author(s):  
Sonia Youhanna ◽  
Lise Bankir ◽  
Paul Jungers ◽  
David Porteous ◽  
Ozren Polasek ◽  
...  

Background: The importance of vasopressin and/or urine concentration in various kidney, cardiovascular, and metabolic diseases has been emphasized recently. Due to technical constraints, urine osmolality (Uosm), a direct reflect of urinary concentrating activity, is rarely measured in epidemiologic studies. Methods: We analyzed 2 possible surrogates of Uosm in 4 large population-based cohorts (total n = 4,247) and in patients with chronic kidney disease (CKD, n = 146). An estimated Uosm (eUosm) based on the concentrations of sodium, potassium, and urea, and a urine concentrating index (UCI) based on the ratio of creatinine concentrations in urine and plasma were compared to the measured Uosm (mUosm). Results: eUosm is an excellent surrogate of mUosm, with a highly significant linear relationship and values within 5% of mUosm (r = 0.99 or 0.98 in each population cohort). Bland-Altman plots show a good agreement between eUosm and mUosm with mean differences between the 2 variables within ±24 mmol/L. This was verified in men and women, in day and night urine samples, and in CKD patients. The relationship of UCI with mUosm is also significant but is not linear and exhibits more dispersed values. Moreover, the latter index is no longer representative of mUosm in patients with CKD as it declines much more quickly with declining glomerular filtration rate than mUosm. Conclusion: The eUosm is a valid marker of urine concentration in population-based and CKD cohorts. The UCI can provide an estimate of urine concentration when no other measurement is available, but should be used only in subjects with normal renal function.


2019 ◽  
Vol 24 (4) ◽  
pp. 179
Author(s):  
Bimo Aji Nugroho ◽  
Mochamad Arief Soendjoto ◽  
Muhammad Zaini

Public awareness and knowledge on mangrove forest biodiversity, especially gastropods, is very limited. This study aims to compare the density and diversity index of gastropod species according to their distance from the coastline and to analyze the relationship of the two with the physical environment around them. Three lanes were placed in the southern part of the mangrove forest. The first lane (LT-1) was placed about 5 m from the coastline towards the sea. The second lane (LT-2) was placed 10 m towards the sea from LT-1 and the third lane (LT-3) was 10 m from LT-2 towards the sea. In each lane there were 10 (1 mx 1 m) plots and the distance between adjacent plots was 10 m. A total of 1.432 Gastropod individuals consisting of 16 species and 7 families were collected from 30 plots. In detail 16 species (927 individuals) were collected from LT-1, 16 species (500 indv) from LT-2, and only 3 species or 5 individuals from LT-3. The density of LT-1, LT-2, and LT-3 species respectively was 92.7; 50.0; and 0.5 indv.m-2, while the diversity index successively was 2.56 (moderate); 2.53 (moderate); and 0.95 (low). Both species density and diversity in lanes that are close to the coastline are higher than in lanes located in the direction of the sea. The base substrate on the path that was close to the coastline was clay, while on the lane that laid in the direction of the sea was sandy loam.


2021 ◽  
Author(s):  
Raphael Viscarra Rossel ◽  
Juhwan Lee ◽  
Mingxi Zhang ◽  
Zhongkui Luo ◽  
YingPing Wang

&lt;p&gt;We simulated soil organic carbon (C) dynamics across Australia with the Rothamsted carbon model ({\sc Roth C}) by connecting new spatially-explicit soil measurements and data with the model. This helped us to bridge the disconnection that exists between datasets used to inform the model and the processes that it depicts. We compiled publicly available continental-scale datasets and pre-processed, standardised and configured them to the required spatial and temporal resolutions. We then calibrated {\sc Roth C} and run simulations to estimate the baseline soil organic C stocks and composition in the 0--0.3~m layer at 4,043 sites in cropping, modified grazing, native grazing, and natural environments across Australia. We used data on the C fractions, the particulate, mineral associated, and resistant organic C (POC, MAOC and ROC, respectively) to represent the three main C pools in the {\sc Roth C} model's structure.&lt;span class=&quot;Apple-converted-space&quot;&gt;&amp;#160; &lt;/span&gt;The model explained 97--98\% of the variation in measured total organic C in soils under cropping and grazing, and 65\% in soils under natural environments. We optimised the model at each site and experimented with different amounts of C inputs to simulate the potential for C accumulation under constant and chainging climate in a 100-year simulation. Soils under native grazing were the most potentially vulnerable to C decomposition and loss, while soils under natural environments were the least vulnerable. An empirical assessment of the controls on the C change showed that climate, pH, total N, the C:N ratio, and cropping were the most important controls on POC change. Clay content and climate were dominant controls on MAOC change. Consistent and explicit soil organic C simulations improve confidence in the model's estimations, contributing to the development of sustainable soil management under global change.&lt;span class=&quot;Apple-converted-space&quot;&gt;&amp;#160;&lt;/span&gt;&lt;/p&gt;


2014 ◽  
Vol 94 (3) ◽  
pp. 389-402 ◽  
Author(s):  
J. J. Miller ◽  
B. W. Beasley ◽  
C. F. Drury ◽  
X. Hao ◽  
F. J. Larney

Miller, J. J., Beasley, B. W., Drury, C. F., Hao, X. and Larney, F. J. 2014. Soil properties following long-term application of stockpiled feedlot manure containing straw or wood-chip bedding under barley silage production. Can. J. Soil Sci. 94: 389–402. The influence of long-term land application of stockpiled feedlot manure (SM) containing either wood-chip (SM-WD) or straw (SM-ST) bedding on soil properties during the barley (Hordeum vulgare L.) silage growing season is unknown. The main objective of our study was determine the effect of bedding material in stockpiled manure (i.e., SM-WD vs. SM-ST) on certain soil properties. A secondary objective was to determine if organic amendments affected certain soil properties compared with unamended soil. Stockpiled feedlot manure with SM-WD or SM-ST bedding at 77 Mg (dry wt) ha−1 yr−1 was annually applied for 13 to 14 yr to a clay loam soil in a replicated field experiment in southern Alberta. There was also an unamended control. Soil properties were measured every 2 wk during the 2011 and 2012 growing season. Properties included water-filled pore space (WFPS), total organic C and total N, NH4-N and NO3-N, water-soluble non-purgeable organic C (NPOC), water-soluble total N (WSTN), denitrification (acetylene inhibition method), and CO2 flux. The most consistent and significant (P≤0.05) bedding effects on soil properties in both years occurred for total organic C, C:N ratio, and WSTN. Total organic C and C:N ratio were generally greater for SM-WD than SM-ST, and the reverse trend occurred for WSTN. Bedding effects on other soil properties (WFPS, NH4-N, NO3-N, NPOC) occurred in 2012, but not in 2011. Total N, daily denitrification, and daily CO2 flux were generally unaffected by bedding material. Mean daily denitrification fluxes ranged from 0.9 to 1078 g N2O-N ha−1 d−1 for SM-ST, 0.8 to 326 g N2O-N ha−1 d−1 for SM-WD, and 0.6 to 250 g N2O-N ha−1 d−1 for the CON. Mean daily CO2 fluxes ranged from 5.3 to 43.4 kg CO2-C ha−1 d−1 for SM-WD, 5.5 to 26.0 kg CO2-C ha−1 d−1 for SM-ST, and from 0.5 to 6.8 kg CO2-C ha−1 d−1 for the CON. The findings from our study suggest that bedding material in feedlot manure may be a possible method to manage certain soil properties.


1985 ◽  
Vol 65 (1) ◽  
pp. 219-223
Author(s):  
R. de JONG ◽  
W. K. SLY

Based on soil water modelling results of 19 stations, averaged long-term soil water reserves on the Canadian Prairies were compared for two soils having available water-holding capacities of 280 and 250 mm. The soil water reserves of the 250-mm capacity soil were 6.5%, 8.7% and 6.2% less than those of the 280-mm capacity soil on 1 May after a fallow year, 30 June heading time and 1 May after a crop year, respectively. The aridity indices for wheat at the soft dough stage for the 250-mm capacity soil ranged from 4% less in the drier part of the Prairies to 7–9% more in the wetter regions as compared to the 280-mm capacity soil. Water deficits for a perennial crop grown on a 280-mm capacity soil could not be used to infer the deficits on a 250-mm capacity soil because of the model’s sensitivity to rainfall distribution with time. Key words: Soil water, modelling, available water-holding capacity


1990 ◽  
Vol 70 (3) ◽  
pp. 471-484 ◽  
Author(s):  
G. E. VERITY ◽  
D. W. ANDERSON

This study examines the cumulative effect of erosion on soil properties that are important to productivity, and estimates the effect of erosion on grain yields. Experiments were located in central Saskatchewan on Dark Brown soils of the Weyburn Association. The relationship between yields and relative distance down eroded hillslopes was described best by a third-order polynominal equation. Grain yields were lowest on the upper slopes and increased steadily through mid-slopes to maximum values that were often double the upper slope yield on the lower or foot slope, then decreased again in the more level parts of the fields away from the slope. The impact of varying degrees of erosion on productivity was estimated by adding back incremental depths of topsoil to eroded knolls. Grain yields were increased by 45–58% by adding 50 mm of topsoil, with additional topsoil (100 or 150 mm) generally increasing yields slightly, but at a decreasing rate. Changes in soil quality with increasing erosion were measured on otherwise similar soils on eroded knolls, with the period of cultivation ranging from 0 (native) to 75 yr. Reductions in the amount of 137Cs in surface horizons with increasing period of cultivation indicated the cumulative effects of erosion, with general soil losses of 20 to 30 Mg ha−1 yr−1. Consistent reductions in silt plus very fine sand fractions with time suggested that wind erosion had been dominant. Organic C and P, total N and S decreased with increasing erosion. Potentially mineralizable N descreased at a faster rate than total N. The CaCO3 content of surface horizons increased, and inorganic P remained constant with increasing degree of erosion. Key words: Nutrients, soil productivity, soil quality, eroded, catena.


1983 ◽  
Vol 1 (2) ◽  
pp. 92-96 ◽  
Author(s):  
Keith Postlethwaite ◽  
Cliff Denton

This paper describes part of a recent piece of research into the identification of pupils who have high potential for performance in specific areas of the academic curriculum in secondary schools. We discuss the relationship of this work to the broader definitions of giftedness which are now of considerable interest, and to the existing studies of identification, which tend to concentrate on high IQ children. We outline a test based method of identifying the pupils who have high potential in a specific subject, and report on the extend of the agreement between identification based on such a test procedure, and that based on teachers' judgements. Finally we draw out some implications of the findings for the way in which identification and provision should inter-relate.


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