scholarly journals Chloride and sulphate solutions as extractants for soil P: II Dependence of the relative extraction power of chloride and sulphate solutions on some soil properties 

1982 ◽  
Vol 54 (4) ◽  
pp. 297-304
Author(s):  
Helinä Hartikainen ◽  
Markku Yli-Halla
Keyword(s):  
Soil Properties ◽  
Opposite Effect ◽  
Extraction Efficiency ◽  
Mineral Soil ◽  
Soil Samples ◽  
Point Of Zero Charge ◽  
Molar Ratio ◽  
Soil P ◽  
Soluble P ◽  
Extraction Power

The relative P extraction power of KCI and K2SO solutions of the same ionic strength was investigated in 102 mineral soil samples. By using the ratio of chloride soluble P to sulphate soluble P (”Cl-P”/”SO4-P”) instead of absolute differences it was possible to find out a more accurate relationship between soil properties and varying extraction efficiency of salt solutions. In the soils of low P intensity, the extractability ratio of P (”Cl-P’/”SO4-P”) seemed to decrease with an increase in the molar ratio of NH4F soluble P (CHANG and JACKSON’s method) to oxalate extractable Al, which indicates the improvement of the relative replacement power of sulphate. Conversely, in the samples of high or medium P intensity an increase in NH4F-P/AI had an opposite effect: the ratio ”Cl-P”/ √(”S04-P”) rather than ”Cl-P”/”SO4-P” was raised, suggesting a marked depression in the efficiency of sulphate. The superiority of sulphate, as compared to chloride, tended to be reduced also with increasing soil pH; the decrease seemed to be the greater the poorer the P status of the soil was. A theory explaining the variation in the relative extraction power of chloride and sulphate solutions was presented and the possible contributory influence of point of zero charge (pzc) was discussed.

scholarly journals Chloride and sulphate solutions as extractants for soil P: III Effect of increasing sulphate concentration on P desorption 

1983 ◽  
Vol 55 (4) ◽  
pp. 363-369
Author(s):  
Helinä Hartikainen ◽  
Markku Yli-Halla
Keyword(s):  
Ionic Strength ◽  
Mineral Soil ◽  
Soil Samples ◽  
Constant Ionic Strength ◽  
Oxide Surfaces ◽  
Promoting Effect ◽  
Soil P ◽  
Sulphate Concentration ◽  
Extraction Power ◽  
P Desorption

The effect of increasing sulphate concentration on P desorption was studied in 102 mineral soil samples with: a) solutions of a constant ionic strength I=0.1 adjusted with KCI and b) 0.1 M and 0.033 M sulphate solutions of different ionic strengths. Further, the efficiency of chloride and sulphate solutions of equal anion concentration (0.1 M) was compared. At a constant ionic strength, P desorption was enhanced as the sulphate concentration of the extractant increased. Even despite a much higher ionic strength the extraction power of the K2SO4 solution was greater than that of the KCI solution of the same anion concentration. Comparison of the 0.1 M and 0.033 M K2SO4 solutions revealed in 53 soil samples the extractability of P to be depressed by an increase in sulphate concentration (and ionic strength). In 49 samples, on the contrary, the 0.1 M K2SO4 solution extracted equal or greater P amounts than did the 0.033 M K2SO4. It was observed that the lower the P coverage on the oxide surfaces in the soil was, the more obviously the promoting effect of increasing sulphate concentration overruled the depression induced by increasing ionic strength, and the more superior the K2SO4 solution was as compared to the KCI solution.

scholarly journals Chloride and sulphate solutions as extractants for soil P: I Effect of ionic species and ionic strength on P desorption 

1982 ◽  
Vol 54 (4) ◽  
pp. 287-296
Author(s):  
Helinä Hartikainen ◽  
Markku Yli-Halla
Keyword(s):  
Ionic Strength ◽  
Extraction Efficiency ◽  
Mineral Soil ◽  
Water Soluble ◽  
Exchange Reactions ◽  
Salt Solutions ◽  
Chloride Solutions ◽  
Soil P ◽  
Water Soluble P ◽  
Soluble P

The effect of Cl and SO2-4, anions as well as that of the ionic strength on the desorption of soil P were studied in 102 mineral soil samples by extracting them with KCI and K2SO4 solutions at ionic strengths of 0.025 and 0.1. The quantities of salt soluble and water soluble P in the soils were compared. Both sulphate solutions extracted more P in every single sample than either of the chloride solutions. On the other hand, the material could be divided into three groups according to the position of water in the order of extraction efficiency. In the group W>S>Cl, consisting of 53 samples, water was the most effective extractant, in the group S>W>Cl of 37 samples water was less effective than sulphate solutions but more effective than the chloride solutions, and in 12 samples (S>Cl>W) water was the least effective, less effective than even chloride. The groups classified according to P extractability did not deviate from each other in terms of soil texture, pH or org. C %, but the salt solutions tended to be the more effective extractants the poorer the P status of the soil was. The salt soluble and water soluble P which are closely related to each other correlated with the same factors. Exclusive of the group of 12 samples (S>Cl>W), the highest value sof correlation coefficient were found for NH4F-P/Al, i.e. the molar ratio of NH4F soluble P (CHANG and JACKSON's method) to oxalate extractable Al (r=0.89***-0.93***). The absolute differences between amounts of P dissolved in KCI and K2SO4 solutions of the same initial ionic strength were the greater the more water soluble P the samples contained (r=0.58* -0.94***). An increase in ionic strength tended to depress the extractability of P in both salt solutions. Therefore the ligand exchange between sulphate and phosphate or hydroxyl was regarded unprobable. A theory of the extraction mechanism of sulphate was presented. The greater extraction efficiency of sulphate was assumed to be caused by the exchange reactions with H2O groups which affect the ionic strength in a solution and the electric condition near the surface.

scholarly journals Effect of decreasing acidity on the extractability of inorganic soil phosphorus

1981 ◽  
Vol 53 (1) ◽  
pp. 16-26 ◽  
Author(s):  
Helinä Hartikainen
Keyword(s):  
Extraction Method ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Soil Phosphorus ◽  
Analytical Data ◽  
Mineral Soil ◽  
Soil Samples ◽  
Inorganic P ◽  
Soil Material ◽  
Soil P

The extractability of P by the water and anion exchange resin methods and reactions of soil inorganic P were investigated with seven acid mineral soil samples incubated with KOH solutions of various concentrations. The results were compared with the analytical data obtained from three soil samples incubated in a prolonged liming experiment. The resin extraction method proved more effective than the water extraction method. The amounts of P desorbed by both methods seemed to increase exponentially as the pH in the soil suspensions rose. The factors involved were discussed. On the basis of fractionation analyses P reacting to changes in the pH and participating in desorption processes was supposed to originate from secondary NH4F and NaOH soluble reserves. In general, as the acidity decreased NH4F-P increased at the expense of NaOH-P. In heavily limed gyttja soil also H2SO4-P increased. This was possibly induced by the precipitation of mobilized P as a Ca compound. The significance of pH in the extractability of soil P seemed somewhat to lessen as the amount of secondary P increased. The results were in accordance with the conception that liming improves the availability of inorganic P to plants and reduces the need for P fertilization. However, increasing of the soil pH involves the risk that P is more easily desorbed to the recipient water by the eroded soil material carried into the watercourse. Therefore, intensive liming is not recommendable close to the shoreline. Further, it should be taken into account that liming of lakes may also result in eutrophication as desorption of sedimentary inorganic P is enhanced.

scholarly journals Uptake of soil P, Al, Fe, Mn, Mg and Ca by Italian rye grass (Lolium multiflorum Lam.) induced by synthetic chelating agent

1981 ◽  
Vol 53 (3) ◽  
pp. 152-160
Author(s):  
Helinä Hartikainen
Keyword(s):  
Dry Matter ◽  
Ethylenediaminetetraacetic Acid ◽  
Lolium Multiflorum ◽  
Mineral Soil ◽  
Chelating Agent ◽  
Soil Samples ◽  
Soil P ◽  
Rye Grass ◽  
Calcium Supply ◽  
The Stability

The effect of a synthetic chelating compound on the dry matter yield and the uptake of soil P, Al, Fe, Mn, Mg and Ca by Italian rye grass was studied in a pot experiment with three mineral soil samples irrigated with water or 0.001 M Na2-EDTA(dinatrium salt of ethylenediaminetetraacetic acid) solution. The Na2-EDTA treatment seemed not to affect the quantity of the dry matter yields, but it affected markedly their chemical composition. Increased contents of P, Al and Fe were found in all the harvests. In two soil samples the P supply was improved by 35—45 %. The accumulation of Al, Fe and Mn induced by Na2-EDTA tended to be the more effective the greater the stability constant for the corresponding metal-EDTA chelate was. Thus, the iron uptake increased most intensively, i.e. by 217—458 %, and that of aluminium by 33—120 %. On the basis of the first two harvests the manganese absorption by the rye grass seemed to decrease probably due to the enormous accumulation of iron. The results also suggested that the addition of Na2-EDTA to the soil was not able essentially to affect the magnesium and calcium supply to the plants.

scholarly journals Effect of cumulative fertilizer dressings on the phosphorus status of mineral soils II Comparison of two phosphorus testing methods

1989 ◽  
Vol 61 (2) ◽  
pp. 61-66
Author(s):  
Helinä Hartikainen
Keyword(s):  
Rating Scale ◽  
Soil Samples ◽  
Water Soluble ◽  
Water Extraction ◽  
Molar Ratio ◽  
Acetate Solution ◽  
Testing Methods ◽  
Water Soluble P ◽  
Soluble P ◽  
The Difference

Soil samples collected from field plots before onset of fertilization trials and after seven years of cultivation with annual P additions of 0, 30 or 60 kg ha-1, were analyzed for water-soluble P (Pw) and acid NH4-acetate-extractable P (PAAc). In all soil samples, the P test values correlated closely (r = 0.93***). However, they differed significantly in the clay soils where PAAc amounted to 59—96 % of Pw . In the coarser soils, the acetate solution extracted 70—365 % of the water-soluble P, but the difference between the methods remained insignificant. In both soil groups, the molar ratio of NH4F-P to oxalate-soluble Al explained 90 % or more of the variation in the P test values. The soil samples were divided into different P content classes according to the acetate test calibration scheme. In various P classes the test values tended to differ statistically significantly: in the lower classes acetate extracted P more and in the higher classes less than water did. Only in soils ranked as satisfactory in P the test values were about equal. When the rating scale limits given for the advisory soil testing were applied to the water extraction, in most soils the difference between the P testing methods was of one P class. The fertilization recommendations based on the acetate and water extraction tests were compared.

scholarly journals Continuous Integrated Process of Biodiesel Production and Purification—The End of the Conventional Two-Stage Batch Process?

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 403
Author(s):  
Matea Bačić ◽  
Anabela Ljubić ◽  
Martin Gojun ◽  
Anita Šalić ◽  
Ana Jurinjak Tušek ◽  
...  
Keyword(s):  
Extraction Efficiency ◽  
Deep Eutectic Solvent ◽  
International Standards ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Process Conditions ◽  
Integrated Process ◽  
Free Glycerol ◽  
Mass Ratio ◽  
Glycerol Content

In this research, optimization of the integrated biodiesel production process composed of transesterification of edible sunflower oil, catalyzed by commercial lipase, with simultaneous extraction of glycerol from the reaction mixture was performed. Deep eutectic solvents (DESs) were used in this integrated process as the reaction and extraction media. For two systems, choline chloride:glycerol (ChCl:Gly) and choline chloride:ethylene glycol (ChCl:EG), respectively, the optimal water content, mass ratio of the phase containing the mixture of reactants (oil and methanol) with an enzyme and a DES phase (mass ratio of phases), and the molar ratio of deep eutectic solvent constituents were determined using response surface methodology (RSM). Experiments performed with ChCl:Gly resulted in a higher biodiesel yield and higher glycerol extraction efficiency, namely, a mass ratio of phases of 1:1, a mass fraction of water of 6.6%, and a molar ratio of the ChCl:Gly of 1:3.5 were determined to be the optimal process conditions. When the reaction was performed in a batch reactor under the optimal conditions, the process resulted in a 43.54 ± 0.2% yield and 99.54 ± 0.19% glycerol extraction efficiency (t = 2 h). Unfortunately, the free glycerol content was higher than the one defined by international standards (wG > 0.02%); therefore, the process was performed in a microsystem to enhance the mass transfer. Gaining the same yield and free glycerol content below the standards (wG = 0.0019 ± 0.003%), the microsystem proved to be a good direction for future process optimization.

Agronomic and environmental soil test phosphorus in manured and non-manured Manitoba soils

2007 ◽  
Vol 87 (1) ◽  
pp. 73-83 ◽  
Author(s):  
D. Kimaragamage ◽  
O O Akinremi ◽  
D. Flaten ◽  
J. Heard
Keyword(s):  
Iron Oxide ◽  
Surface Soil ◽  
Single Equation ◽  
Soil Samples ◽  
Soil Test ◽  
Regression Equations ◽  
Soil P ◽  
Soil Test Phosphorus ◽  
Bray 1 ◽  
Water Extractable

Quantitative relationships between soil test phosphorus (STP) methods are needed to guide P management especially in manured soils with high P. Our objectives were: (i) to compare amounts of P extracted by different methods; (ii) to develop and verify regression equations to convert results among methods; and (iii) to establish environmental P thresholds for different methods, in manured and non-manured soils of Manitoba. We analyzed 214 surface soil samples (0–15 cm), of which 51 had previous manure application. Agronomic STP methods were Olsen (O-P), Mehlich-3 (M3-P), Kelowna-1 (original; K1-P), Kelowna-2 (modified; K2-P), Kelowna-3 (modified; K3-P), Bray-1 (B1-P) and Miller and Axley (MA-P), while environmental STP methods were water extractable (W-P), Ca Cl2 extractable (Ca-P) and iron oxide impregnated filter paper (FeO-P) methods. The different methods extracted different amounts of P, but were linearly correlated. For an O-P range of 0–30 mg kg-1, relationships between O-P and other STP were similar for manured and nonmanured soils, but the relationships diverged at higher O-P levels, indicating that one STP cannot be reliably converted to another using a single equation for manured and non-manured soils at environmentally critical P levels (0–100 mg kg-1 O-P). Suggested environmental soil P threshold ranges, in mg P kg-1, were 88–118 for O-P, 138–184 for K1-P, 108–143 for K2-P, 103–137 for K3-P, 96–128 for B1-P, 84–111 for MA-P, 15–20 for W-P, 5–8 for Ca-P and 85–111 for FeO-P. Key words: Phosphorus, soil test phosphorus, manured soils, non-manured soils, environmental threshold

scholarly journals Water-dispersible clay in soils treated with sewage sludge

2010 ◽  
Vol 34 (5) ◽  
pp. 1527-1534 ◽  
Author(s):  
João Tavares Filho ◽  
Graziela Moraes de Césare Barbosa ◽  
Adriana Aparecida Ribon
Keyword(s):  
Sewage Sludge ◽  
Block Design ◽  
Clay Fraction ◽  
Organic Matter Content ◽  
Soil Samples ◽  
Point Of Zero Charge ◽  
Native Forest ◽  
Water Dispersible ◽  
Significant Difference ◽  
Dispersible Clay

A by-product of Wastewater Treatment Stations is sewage sludge. By treatment and processing, the sludge is made suitable for rational and environmentally safe use in agriculture. The aim of this study was to assess the influence of different doses of limed sewage sludge (50 %) on clay dispersion in soil samples with different textures (clayey and medium). The study was conducted with soil samples collected from native forest, on a Red Latosol (Brazilian classification: Latossolo Vermelho distroférrico) loamy soil in Londrina (PR) and a Red-Yellow Latosol (BC: Latossolo Vermelho-Amarelo distrófico) medium texture soil in Jaguapitã (PR). Pots were filled with 3 kg of air-dried fine earth and kept in greenhouse. The experiment was arranged in a randomized block design with six treatments: T1 control, and treatments with limed sewage sludge (50 %) as follows: T2 (3 t ha-1), T3 (6 t ha-1), T4 (12 t ha-1), T5 (24 t ha-1) and T6 (48 t ha-1) and five replications. The incubation time was 180 days. At the end of this period, the pots were opened and two sub-samples per treatment collected to determine pH-H2O, pH KCl (1 mol L-1), organic matter content, water-dispersible clay, ΔpH (pH KCl - pH-H2O) and estimated PZC (point of zero charge): PZC = 2 pH KCl - pH-H2O, as well as the mineralogy of the clay fraction, determined by X ray diffraction. The results showed no significant difference in the average values for water-dispersible clay between the control and the other treatments for the two soil samples studied and ΔpH was the variable that correlated best with water-dispersible clay in both soils.

scholarly journals Soil phosphorus availability and soybean response to phosphorus starter fertilizer

2014 ◽  
Vol 38 (5) ◽  
pp. 1487-1495 ◽  
Author(s):  
Ciro Antonio Rosolem ◽  
Alexandre Merlin
Keyword(s):  
Soil Phosphorus ◽  
Soil Surface ◽  
Tropical Soils ◽  
P Fertilization ◽  
Soil P ◽  
Brachiaria Ruziziensis ◽  
Soluble P ◽  
Surface Spread ◽  
P Sources

Phosphorus fixation in tropical soils may decrease under no-till. In this case, P fertilizer could be surface-spread, which would improve farm operations by decreasing the time spend in reloading the planter with fertilizers. In the long term, less soluble P sources could be viable. In this experiment, the effect of surface-broadcast P fertilization with both soluble and reactive phosphates on soil P forms and availability to soybean was studied with or without fertilization with soluble P in the planting furrow in a long-term experiment in which soybean was grown in rotation with Ruzigrass (Brachiaria ruziziensis). No P or 80 kg ha-1 of P2O5 in the form of triple superphosphate or Arad reactive rock phosphate was applied on the surface of a soil with variable P fertilization history. Soil samples were taken to a depth of 60 cm and soil P was fractionated. Soybean was grown with 0, 30, and 60 kg ha-1 of P2O5 in the form of triple phosphate applied in the seed furrow. Both fertilizers applied increased available P in the uppermost soil layers and the moderately labile organic and inorganic forms of P in the soil profile, probably as result of root decay. Soybean responded to phosphates applied on the soil surface or in the seed furrow; however, application of soluble P in the seed furrow should not be discarded. In tropical soils with a history of P fertilization, soluble P sources may be substituted for natural reactive phosphates broadcast on the surface. The planting operation may be facilitated through reduction in the rate of P applied in the planting furrow in relation to the rates currently applied.

EFFECTS OF LIME ON EXTRACTABLE ALUMINUM AND OTHER SOIL PROPERTIES AND ON BARLEY AND ALFALFA GROWN IN POT TESTS

1972 ◽  
Vol 52 (3) ◽  
pp. 427-438 ◽  
Author(s):  
A. J. MacLEAN ◽  
R. L. HALSTEAD ◽  
B. J. FINN
Keyword(s):  
Plant Growth ◽  
Soil Properties ◽  
Soil Ph ◽  
Acid Soil ◽  
Soil Samples ◽  
Neutral Salt ◽  
Incubation Experiment ◽  
Pot Experiments ◽  
P Content ◽  
Mn Content

Liming of six acid soil samples in an incubation experiment with rates to raise the soil pH to 6.0 or above eliminated Al soluble in 0.01 M CaCl2, reduced soluble Mn and Zn, increased NO3-N markedly, and at the highest pH increased the amounts of NaHCO3-soluble P in some of the soils. In corresponding pot experiments, liming increased the yield of alfalfa and in three of the soils the yield of barley also. Liming reduced the concentrations of the metals in the plants and at the highest pH tended to increase the P content of the plants. Liming to a pH of about 5.3 eliminated or greatly reduced soluble Al and the soils were base saturated as measured by the replacement of Al, Ca, and Mg by a neutral salt. There was some evidence that liming to reduce soluble Al and possibly Mn was beneficial for plant growth. Gypsum increased the concentrations of Al, Mn, and Zn in 0.01 M CaCl2 extracts of the soils whereas phosphate reduced them. The changes in the Mn content of the plants following these treatments were in agreement with the amounts of Mn in the CaCl2 extracts.

Sign in / Sign up

Export Citation Format

Share Document