Influence of manure application on extractable potassium in a range of prairie soils

Non-Peer ReviewedIncreasing use of animal manures in Saskatchewan requires information on the effect of manure addition on soil K availability. To address this issue, we examined the effects of repeated application of liquid and solid manure at low and high rates on extractable potassium in soils from four different long-term field trials in Saskatchewan and on K uptake by plants growing on the soils. After four to seven years of manure application, extractable potassium in the soils was significantly increased, with Kelowna extractable K (0-15 cm) increasing from 500 - 600 kg K ha-1 to over 1,000 kg K ha-1 at medium to high rates of annual addition (6,000 - 10,000 gpa swine manure and 15 -30 T ha-1 cattle manure). The K concentration and uptake by the cereal crops was also increased

Use of ion-exchange membranes in routine soil testing

Non-Peer ReviewedWe developed and assessed a method for simultaneous ·extraction of plant available nitrogen, phosphorus, sulfur, and potassium using anion- and cation-exchange membranes (ACEM). The technique was found to be highly suitable for routine soil testing due to its simplicity, rapidness and accuracy. The study compared the amount of nutrients extracted by ACEM with conventional chemical-based extractants for P and K (0.5M NaHCO3) and N and S (0.001M CaCl) for 135 soil samples representing a wide range of soil types in western Canada. The nutrient availability predicted by ACEM was significantly correlated with the conventional methods. The correlation was not affected by the two different shaking times tested (one hour and 15 minutes), suggesting that extraction times as short as 15 minutes could be used in ACEM extraction. To evaluate the relative ability of ACEM and the conventional tests to predict actual nutrient availability to plants, canola plants were grown on soils in the growth chamber and actual plant uptake was compared to test-predicted nutrient availability. Phosphorus and potassium uptake by canola plants was more closely correlated with ACEM extractable P and K (r2= 0.84*** and 0.54***) than with 0.5M NaHCO3 P and K (r2= 0.70*** and 0.37***). Also, nitrogen and sulfur uptake by canola plants was significantly correlated with ACEM extractable-N and SO4 (r2 = 0.60*** and 0.70***) and with CaCl extractable-NO3 and SO4 (r2 = 0.57*** and 0.61 ***). Availability of all four macronutrients can be assessed in a single ACEM extraction. The higher correlation with plant uptake suggests that ACEM is a better index of macro-nutrient availability than conventional methods. The ACEM soil test could be readily adopted in routine soil analysis because of low cost and simplicity as well as its consistency over a wide range of soil types

Evaluation of nitrogen availability from different manure amendments with different C:N ratios

Non-Peer ReviewedA growth chamber study was conducted on two Saskatchewan soils to assess the effect of application of different types of animal manure with different C:N ratios on canola yield and nitrogen uptake. Treatments consisted of 13 different manure amendments with large variance of C:N ratio added at a rate of 100 mg N kg-1. Addition of the solid manure amendments in two soils generally did not result in large increases in canola yield and N uptake, except for two amendments with a C:N of about 7. Generally, cattle manures had little impact on short-term release of available N if the organic C:N ratio was in the range of 13-15 and tended to decrease N availability in the short-term if the organic C:N ratio was over 15. The N supply rate measured by anion-exchange membrane was quite well correlated with plant N uptake differences obtained among the treatments

Effect of a new physiotherapy concept on bone mineral density, muscle force and gross motor function in children with bilateral cerebral palsy

Copyright @ 2010 The Authors.Objective: The purpose of this study was to determine the effect of a new physiotherapy concept on bone density, muscle force and motor function in bilateral spastic cerebral palsy children. Methods: In a retrospective data analysis 78 children were analysed. The concept included whole body vibration, physiotherapy, resistance training and treadmill training. The concept is structured in two in-patient stays and two periods of three months home-based vibration training. Outcome measures were dual-energy x-ray absorption (DXA), Leonardo Tilt Table and a modified Gross Motor Function Measure before and after six months of training. Results: Percent changes were highly significant for bone mineral density, -content, muscle mass and significant for angle of verticalisation, muscle force and modified Gross Motor Function Measure after six months training. Conclusions: The new physiotherapy concept had a significant effect on bone mineral density, muscle force and gross motor function in bilateral spastic cerebral palsy children. This implicates an amelioration in all International Classification of Functioning, Disability and Health levels. The study serves as a basis for future research on evidence based paediatric physiotherapy taking into account developmental implications

Ion-exchange resin strips as plant root simulators

Non-Peer ReviewedIon-exchange resin strips have the potential to closely mimic the manner in which a plant root removes nutrient ions from the surrounding soil. A method was developed involving burial of resin strips in soil; followed by a de-ionized water and dilute HCl wash of the strips. In approximately 200 soil samples obtained from across Saskatchewan, the plant availability of nitrate, ammonium, phosphate, potassium and sulphate as predicted by resin strip burial was significantly correlated with the plant availability predicted by conventional chemical-based soil extractions. Growth chamber experiments were set up in which canola plants were grown on the soils and actual plant nutrient uptake compared to test-predicted availability. The ability of the resin strip burial to predict differences in availability of N and P to canola was similar to the conventional soil extractants, but for K and S the strip burial appeared to be a better predictor of observed differences in plant uptake

Impact of repeated addition of swine manure and cattle manure on Cu and Zn amount and distribution in a Saskatchewan soil

Non-Peer ReviewedIncreasing use of animal manures in Saskatchewan requires information on the fate and distribution of residual manure copper (Cu) and zinc (Zn) in Saskatchewan soils. To address this issue, the amounts of soil Cu and Zn in various inorganic and organic fractions were investigated in a field crop research plot (Cudworth association soil) with a five year history of annual application of liquid swine manure and solid cattle manure, and in two grassland field research plots (Meota and Oxbow association soils) that had received annual application of liquid swine manure for three years. The annual rates of manure application were based on N contents in the manures, and were equivalent to approximately 0, 100, 200 and 400 kg total N ha-1 yr-1 in the field crop plots, and 0 and 100 kg total N ha-1 yr-1 in grassland plots. In both the field crop and grassland manured plots there were no substantial increases in total Cu and Zn in soils associated with manure application. Some increases in the moderately labile Cu and Zn fractions were observed in treatments with large amounts of animal manures applied every year. The liquid swine manure had less effect on increasing labile Cu and Zn fractions than cattle manure. These results indicate that annual addition of animal manures at rates of approximately 100 kg N ha-1 for 3 to 5 years does not constitute an environmental risk from Cu and Zn loading in these soils

Estimating nutrient release from soil organic matter using ion-exchange membranes

Non-Peer ReviewedA simple method was developed to assess mineralizable soil organic N and S using anion-exchange membrane (AEM) burial. With this method, strips of AEM were buried in the soil and used to absorb nitrate and sulfate ions released from organic matter during the incubation of field-moist soil in plastic vials. An index of mineralization was obtained by subtracting initial AEM extractable ion from the ion absorbed on an AEM strip removed at the end of incubation. The mineralization index was compared to a reference method using the same incubation system but with 0.001M CaCl2 solution to extract nitrate and sulfate. A total of 67 soil samples were used which provided a range of soil properties. Results showed the AEM incubation to be simple and to be more closely correlated with plant N and S uptake (r2 = 0.862**** for N and 0.920**** for S) than the reference method (r2 = 0.602**** for N and 0.682**** for S)

Phosphorus loading and environmental analysis in manured Saskatchewan soils

Non-Peer ReviewedPhosphorus (P) is a key element in plant nutrition, but excessive amounts can accumulate in the soil if manure P application rates exceed crop uptake over time. Risk of potential P movement and contamination of surface waters is directly related to the soluble P content of the surface soil. Thus it is important to have an accurate and efficient method of analysis that can be utilized for both agronomic and environmental purposes. On four long-term (five to eight years of annual application) manure research sites in Saskatchewan, four assessments of labile P in soils were compared: sodium bicarbonate extractable, water extractable, anion exchange membrane (PRS™-probes) supply rate, and Modified Kelowna (MK) extractable on soils that received annual manure application rates in excess of recommended levels. All methods were highly correlated with one another, with the exception of MK. The soil P indices increased with manure P application rate and were correlated with plant P concentration and uptake

Soil respiration and nitrous oxide production in distillers grain and glycerol amended soil

Non-Peer ReviewedApplying by-products of biofuel production to soil may be an alternative use to take direct advantage of nutrients and carbon contained within. Ethanol production results in distiller grain and biodiesel produces glycerol as by-product. However, no information currently exists on the effects of adding these amendments on evolution of carbon dioxide and nitrous oxide from soils, yet is important to complete our understanding of potential impacts of biofuel production on greenhouse gas budgets as well as soil quality. Pots containing soil amended with different rates of wet distillers grain, thin stillage, and glycerol were placed in incubation chambers and incubated for 10 days. Treatments of alfalfa powder and urea were added at the same rates of total N as the by-products for comparative purposes. Carbon dioxide and nitrous oxide evolved from amended soil was measured. The alfalfa powder and wet distillers grain resulted in the greatest evolution of CO2 from the soil, with the thin stillage resulting in less CO2 evolved per unit of nitrogen added. Addition of nitrogen fertilizer along with glycerol enhanced microbial activity and decomposition. Per unit of nitrogen added, urea tended to result in the greatest N2O produced, followed by wet distillers grain and thin stillage, with glycerol and dehydrated alfalfa resulting in the lowest nitrous oxide production

Effect of forage legumes on phosphorus availability to the following wheat crop in a Black Chernozem

Non-Peer ReviewedIncluding forage legumes in rotation with annual crops could increase phosphorus (P) availability to the annual crop due to their deep roots and intensive mycorrhizal infection. However, the benefit of forage legumes to increase soil P availability to the subsequent crop has gained less attention in the western Canada. The aim of this study was to investigate the impact of short rotation forage legumes on P availability to the following crop. Forage legumes evaluated in this study were red clover and alfalfa in comparison to an annual legume (pea) and non-legume (flax). The study was conducted at four sites across Saskatchewan. This poster reports on the results at one site near Melfort, SK. In this experiment, two-year alfalfa rotation produced the highest (P = 0.015) biomass yield. Inclusion of short rotation forage legumes had positive impact on wheat grain yield (P < 0.001) , but it did not affect wheat straw P uptake (P = 0.76). The amounts of soil P fractions extracted from all treatments were generally similar. The results suggested that a two year rotation of legumes may be too short a time period to significantly enhance in soil P availability to the following crop