scholarly journals Increased vegetation ground cover reduces water, sediment and phosphorus losses in Cambisol treated with swine slurry

2021 ◽  
Vol 20 (3) ◽  
pp. 222-230
Author(s):  
Patrícia Pretto Pessotto ◽  
Luciano Colpo Gatiboni ◽  
Daniel João Dall Orsoletta ◽  
Gilmar Luiz Mumbach ◽  
Daniel Alexandre Iochims
Keyword(s):  
Crop Residues ◽  
Ground Cover ◽  
Swine Slurry ◽  
Runoff Volume ◽  
Simulated Rain ◽  
Soluble P ◽  
Four Levels ◽  
Phosphorus Losses ◽  
Total P

This study aims to evaluate the influence of the ground cover rate by crop residues and the rain time elapsed after the application of liquid swine slurry (LSS) under losses of water, sediments, and phosphorus (P). The study was carried out under a Humic Cambisols. Two areas were delimited: with and without the application of LSS. Each area was subdivided into four levels of crop residues: 5%, 35%, 65%, and 95%. Vegetable residues present in the area, from corn and black oat, were used. Three collecting gutters of 0.60 m² were installed in each subplot. Simulated rain was carried out on these, and the runoff volume collected for quantification and determination of losses. With LSS application, increase in the cover rate by crop residues reduces 0.3 mm h-1 the runoff volume and 1.67 mg m-2 reactive soluble P (H2O-P). The sediment losses in the first collection after the beginning of the rain were 23 times lower in the soil with 95% ground cover than in the soil with 5% ground cover. The loss of total P (total-P) decreases with the increase of the ground cover of the soil and increases in the same way with the increase of the time.

Determination of Phosphorus and Potassium in Commercial Inorganic Fertilizers by Inductively Coupled Plasma–Optical Emission Spectrometry: Single-Laboratory Validation, First Action 2015.18

2016 ◽  
Vol 99 (4) ◽  
pp. 914-922 ◽  
Author(s):  
Nancy J Thiex
Keyword(s):  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Emission Spectrometry ◽  
Official Method ◽  
Inductively Coupled ◽  
Plasma Optical Emission Spectrometry ◽  
Soluble P ◽  
Single Laboratory ◽  
Total P

Abstract A previously validated method for the determination of both citrate–EDTA-soluble P and K and acid-soluble P and K in commercial inorganic fertilizers by inductively coupled plasma–optical emission spectrometry was submitted to the expert review panel (ERP) for fertilizers for consideration of First Action Official MethodSM status. The ERP evaluated the single-laboratory validation results and recommended the method for First Action Official Method status and provided recommendations for achieving Final Action. Validation materials ranging from 4.4 to 52.4% P2O5 (1.7–22.7% P) and 3–62% K2O (2.5–51.1% K) were used for the validation. Recoveries from validation materials for citrate-soluble P and K ranged from 99.3 to 124.9% P and from 98.4 to 100.7% K. Recoveries from validation materials for acid-soluble “total” P and K ranged from 95.53 to 99.40% P and from 98.36 to 107.28% K. Values of r for citrate-soluble P and K, expressed as RSD, ranged from 0.28 to 1.30% for P and from 0.41 to 1.52% for K. Values of r for total P and K, expressed as RSD, ranged from 0.71 to 1.13% for P and from 0.39 to 1.18% for K. Based on the validation data, the ERP recommended the method (with alternatives for the citrate-soluble and the acid-soluble extractions) for First Action Official Method status and provided recommendations for achieving Final Action status.

Determination of true ileal phosphorus digestibility of maize and soybean meal and true ileal calcium digestibility of soybean meal for broiler chickens

2019 ◽  
Vol 59 (4) ◽  
pp. 681 ◽  
Author(s):  
T. Trairatapiwan ◽  
Y. Ruangpanit ◽  
O. Songserm ◽  
S. Attamangkune
Keyword(s):  
Soybean Meal ◽  
Broiler Chickens ◽  
Linear Regression Analysis ◽  
Regression Method ◽  
Broiler Chicks ◽  
Ca Deficiency ◽  
Four Levels ◽  
Dietary Treatments ◽  
Total P

Two experiments were conducted, using the regression method, to determine the true ileal phosphorus (P) digestibility of maize and soybean meal (SBM), and true ileal calcium (Ca) digestibility of SBM for broiler chickens. The aim of Experiment 1 was to determine true ileal P digestibility of maize and SBM. The experimental diets were formulated with four inclusion levels of each test ingredient to achieve graded concentrations of total P (2.5, 3.0, 3.5 and 4.0 g/kg, respectively). The P concentrations in maize-based diets were adjusted by the inclusion of monosodium phosphate. The Ca:total P ratio in all diets was maintained at 1.35 by the addition of limestone. Experiment 2 was conducted to determine true ileal Ca digestibility of SBM. Experimental diets were formulated to contain four levels of SBM to achieve graded concentrations of Ca (2.5, 3.0, 3.5 and 4.0 g/kg, respectively). Because of the low concentration of Ca in SBM, all diets were supplemented with a similar level of limestone to prevent any Ca deficiency. The Ca:total P ratio in all diets was adjusted to be equal by the addition of monosodium phosphate. In both experiments, titanium dioxide (3 g/kg) was used as the indigestible marker. One-day-old male broiler chicks were fed a commercial starter diet from 1 to 21 days of age. On Day 22, a total of 240 and 120 birds were assigned to eight and four dietary treatments in Experiments 1 and 2, respectively, with five replicate cages and six birds per cage. Birds were fed the experimental diets for 7 days. On Day 29, ileal digesta were collected from the posterior half of ileum, and the true P and Ca digestibility of test ingredients were calculated by linear regression analysis. True P digestibility of maize and SBM were determined to be 33.8% and 42.3%, respectively. True Ca digestibility of SBM was determined to be 45.9%.

scholarly journals Phosphorus Speciation in Surface Waters by Ion Chromatography With High Resolution Mass Spectrometry Detection

2021 ◽  
Author(s):  
Vlastimil Packa
Keyword(s):  
Mass Spectrometry ◽  
Ion Chromatography ◽  
High Resolution Mass Spectrometry ◽  
Ground Surface ◽  
Analytical Determination ◽  
Water Quality Control ◽  
Accuracy Of Measurements ◽  
Total P ◽  
Inorganic And Organic

Phosphorus (P) containing compounds, depending on their origin, can enter freshwater systems in variety of forms. Utilization of bioavailable P, a key nutrient in living organisms, is a crucial factor in biological productivity in aquatic environment¹. An increase in the P concentration in water, resulting from both natural and anthropogenic processes, can lead to eutrophication and an excessive growth of vegetative biomass. Determination of organic and inorganic P species in ground, surface and waster is an important part of water quality control and monitoring². Analytical determination of P compounds, quantification, identification (Chapter 2) and P speciation process can be problematic due to P adsorption on storage containers, sulfate interference, presence of acid hydrolysable P species and colloidal matter, association of both inorganic and organic phosphates with iron, manganese and aluminum, biological uptake of P. Such processes have to be considered when designing an analytical procedure for analysis of P species. Analytical P compound separation by ion chromatography with mass spectrometry/Orbitrap technology for compound detection (Chapter 3) is a powerful technology with highly sensitive and selective properties capable of performing P speciation in one analytical run. Selectivity of the Orbitrap detector also allows for utilization of isotope dilution technique which can compensate for loss of P compounds during storage and transportation and thus increase accuracy of measurements and holding time of sample matrices. Analytical techniques used in the past were able to determine broad P-fractions, such as total P, total P or functional groups of inorganic and organic P compounds. Identification of variety of specific P-containing compounds of inorganic and organic origin by the methodology used in this thesis in combination with multivariate statistical analysis can be used to explain the large sets of intercorrelated analytical variables with a smaller set of independent variables (Chapter 4) and help in source identification in water pollution studies³.

Investigation of Rotational Relaxation by Double Resonance and Stark Switch Techniques

1980 ◽  
Vol 35 (8) ◽  
pp. 832-840
Author(s):  
W. Schrepp ◽  
H. Dreizler ◽  
A. Guarnieri
Keyword(s):  
Double Resonance ◽  
Relaxation Times ◽  
Experimental Methods ◽  
Rotational Relaxation ◽  
Triple Resonance ◽  
Static Electric Field ◽  
First Order ◽  
Four Levels ◽  
Relative Change

Abstract For the four rotational levels JK₋K₊ = 101, 110,212 and 221 of ethylene oxide all possible four level double resonance experiments for dipole allowed transitions have been performed to investigate collisional effects and to determine the relative change of signal intensity, η = ⊿I/I, due to high power pump radiation. The T1 and T2-relaxation times have been measured for all dipole allowed transitions within these four levels. A combination of the data obtained from both experimental methods allows the determination of rate and bath constants taking into account only first order dipolar transitions. No further restrictions have been used. This approximation is supported by a triple resonance experiment. In addition to the pure gas investigation in the absence of external fields, rotational relaxation has been studied in the presence of a static electric field and in a mixture with hydrogen.

Plant Community Structure and Composition in Uneven-aged Stands of Loblolly-Shortleaf Pine at Four Basal Area Levels

1995 ◽  
Vol 19 (2) ◽  
pp. 84-88 ◽  
Author(s):  
Philip A. Tappe ◽  
Michael D. Cain ◽  
T. Bently Wigley ◽  
Derik J. Reed
Keyword(s):  
Community Structure ◽  
Plant Community ◽  
Basal Area ◽  
Ground Cover ◽  
Control Treatment ◽  
Plant Community Structure ◽  
Shortleaf Pine ◽  
Single Tree ◽  
Single Tree Selection ◽  
Four Levels

Abstract The effects of overstory pine basal area on plant community structure and composition were assessed in uneven-aged stands of loblolly and shortleaf pines (Pinus taedaL. and P. echinata Mill.) in southern Arkansas. Basal area treatments were 40, 60, 80, and 100 ft2/ac for the merchantable pine component (>3.5 in. dbh) and were maintained on a 6 yr cutting cycle using single-tree selection. Assessments of plant communities were made 10 yr after a single hardwood control treatment. The four levels of pine basal area had no effect on percent ground cover of most plants <3 ft tall, but ground cover from graminoids decreased as pine basal area increased. Vertical cover above loft height increased 33% as overstory basal area increased from 40 to 100 ft2/ac, but basal area had no effect on horizontal cover in height zones between 0 and 10ft. It is concluded that uneven-aged stands of loblolly-shortleaf pine with merchantable basal areas of from 40 to 100 ft²/ac may support similar plant species in the understory and consequently probably provide similar habitat requirements for a variety of game and nongame wildlife. South. J. Appl. For. 19(2):84-88.

Contrast and Size Variables and the Tilt After-effect

1972 ◽  
Vol 24 (1) ◽  
pp. 1-7 ◽  
Author(s):  
D. M. Parker
Keyword(s):  
Test Grating ◽  
After Effect ◽  
Four Levels ◽  
The Relationship

The relationship between the contrast and bar width of adapting and test gratings in the determination of the magnitude of the tilt after-effect was explored. When the contrast of adapting and test gratings is varied concomitantly over four levels, the magnitude of the tilt after-effect does not change. When the contrast of the adapting grating is higher than the test grating, the magnitude of the after-effect is increased and when its contrast is lower than the test grating, the magnitude of the after-effect is decreased. When the bar width of the test grating is narrower or broader than that of the adapting grating, the magnitude of the after-effect does not change. The implications of these results for a neurophysiological explanation of the tilt after-effect are discussed.

Phosphorus in runoff from a fertile dairy pasture

Soil Research ◽  
1997 ◽  
Vol 35 (2) ◽  
pp. 419 ◽  
Author(s):  
David Nash ◽  
Craig Murdoch
Keyword(s):  
Ascorbic Acid ◽  
Control Measures ◽  
Late Winter ◽  
Water Runoff ◽  
High Fertility ◽  
Runoff Water ◽  
Runoff Volume ◽  
Total Runoff ◽  
P Concentration ◽  
Total P

Losses of phosphorus (P) from grazed pastures in runoff can significantly reduce the water quality in streams draining agricultural catchments. Many preventative strategies depend for their success on the association of the P with large soil particles (>0·45 mm). We investigated the forms of P in runoff from a dairy pasture of high fertility. A 3·6-ha paddock at Darnum in West Gippsland, Victoria, was set up to measure runoff volume and rainfall, and to sample runoff water. Runoff from the site was restricted to 3 months in late winter and spring. Total runoff for 1994 of 660 m3 had an average total P concentration of 5·2 mg/L. Runoff from a single storm system over 8 days in early November accounted for 56% of the total runoff volume and 69% of the P lost. Of the total P in the runoff, 93% passed through a filter with 0·45-µm pores and 91% was reactive in an ascorbic acid–molybdate medium, without digestion; 89% of the P was both reactive in the ascorbic acid{molybdate medium and in the <0·45-µm fraction. There was no apparent relationship (P > 0·05) between P concentration and soil cover. In the Darnum catchment, the major runoff events occurred when the soil was saturated. The low settling velocities of materials <0·45 µm and the amount of P moving in larger storms would suggest that buffer strips and riparian zones are unlikely to decrease P losses substantially from dairy pastures in this area. Further, since erosion is unlikely to be the major process by which P is lost, control measures which simply limit erosion will be similarly ineffective at preventing P losses under the conditions that prevailed in this study.

Sign in / Sign up

Export Citation Format

Share Document