AN INVESTIGATION ON THE DEPENDENCE OF THE GAPON COEFFICIENT ON EXCHANGEABLE SODIUM BY THREE LINEAR TRANSFORMATIONS

1988 ◽  
Vol 68 (4) ◽  
pp. 813-820
Author(s):  
V. P. EVANGELOU ◽  
F. J. COALE
Keyword(s):  
Clay Minerals ◽  
Limited Range ◽  
Selectivity Coefficient ◽  
Sodium Adsorption Ratio ◽  
Exchangeable Sodium ◽  
Linear Transformations ◽  
Laboratory Staff ◽  
Soil Systems ◽  
Exchange Adsorption ◽  
Exchange Selectivity

Based on theorical considerations of ideal exchangers, the traditional Gapon exchange selectivity coefficient (KG) is generally not expected to remain constant for exchangeable sodium ratio (ESR) greater than 0.20. Therefore, the ESR-SAR (SAR=sodium adsorption ratio) relationship is only expected to be linear and predictable for this limited range of exchange sites. The purpose of this study is to demonstrate that for some soils and/or clay minerals, which are considered nonideal exchangers, the KG may remain constant for ESR values greater than 0.20. This information is important for the reclamation of sodic soil systems with ESR > 0.2 to near Na+ saturation. Experimental data in the literature is most often limited in the ESR range of 0 – 1. Experimental Na+-Ca2+ exchange data for each of a number of soils and clay minerals were plotted according to three linear transformations of the Gapon expression in order to determine if a particular soil or clay mineral exhibits a constant Gapon exchange selectivity coefficient (KG) for ESR values significantly greater than 0.20. The three linear transformations are represented by plots of (1) 1/ExNa vs. 1/SAR, (2) ExNa vs. ExNa/SAR and (3) SAR/ExNa vs. SAR (ExNa = exchangeable Na). From the three plots employed, the ExNa vs. ExNa/SAR and the SAR/ExNa vs. SAR were shown to be the most applicable in predicting a constant KG for ESR values greater than 0.20. It is also shown that some generally low CEC materials may exhibit a constant KG for ESR values significantly greater than 0.20. These data also infer that for a particular soil the linearity of the widely used ESR-SAR relationship introduced by the U.S. Salinity Laboratory Staff may not be limited to an ESR value of 0.20. Key words: Exchangeable sodium percentage, sodium adsorption ratio, thermodynamics of cation exchange, adsorption maxima, ion affinity constants.

SOIL CHEMICAL CRITERIA FOR IRRIGATION SUITABILITY CLASSIFICATION OF BROWN SOLONETZIC SOILS

1988 ◽  
Vol 68 (4) ◽  
pp. 703-714 ◽  
Author(s):  
D. R. BENNETT
Keyword(s):  
Selectivity Coefficient ◽  
Sodium Adsorption Ratio ◽  
Exchangeable Cations ◽  
Statistical Relationship ◽  
Exchangeable Sodium ◽  
Irrigation Suitability ◽  
Saturation Extract ◽  
Solonetzic Soil ◽  
Southern Alberta

A good statistical relationship was obtained between the exchangeable-sodium ratio and the sodium adsorption ratio (SAR) in Brown Solonetzic and associated soils in southern Alberta. Reliable estimates of the exchangeable-sodium status of these sulfate-rich soils may be anticipated when SAR values are less than 20. Prediction of the exchangeable-sodium status of soils on the basis of SAR values is preferable for both Solonetzic soil and irrigation suitability classification. A saturation extract SAR value of five in the B horizon generally corresponds to an exchangeable calcium to sodium ratio of 10. Saturation extract SAR values of five and 12 are recommended as revised soil chemical criteria for Brown Solonetzic soil and irrigation suitability classification, respectively. Key words: Solonetzic soils, exchangeable cations, sodium adsorption ratio, selectivity coefficient, irrigation suitability

EFFECT OF TOTAL CATION CONCENTRATION AND SODIUM ADSORPTION RATIO ON EXCHANGEABLE SODIUM RATIO

1982 ◽  
Vol 62 (1) ◽  
pp. 177-185 ◽  
Author(s):  
E. J. DOERING ◽  
S. D. MERRILL ◽  
W. O. WILLIS
Keyword(s):  
Soil Solution ◽  
Regression Line ◽  
Sodium Adsorption Ratio ◽  
High Salt ◽  
Exchangeable Sodium ◽  
Salt Solutions ◽  
Sodic Soils ◽  
Laboratory Staff ◽  
Cation Concentration ◽  
The U.S

Replicated analyses for each of five levels of total cation concentration showed that exchangeable sodium ratio (ESR) and sodium adsorption ratio (SAR) were linearly related by equations of the form ESR = a + b (SAR). The coefficient, b, decreased from 0.0163 to 0.0085 as total cation concentration increased from 39 to 1057 meq/L, showing that the equilibrium of exchange, as measured by ESR and SAR, is strongly affected by total cation concentration of the soil solution. A regression line, previously published by the U.S. Salinity Laboratory Staff, lies between the regression lines for 39 and 110 meq/L. Exchangeable sodium ratio can be inferred from SAR alone as long as SAR is not larger than about 20. However, the error of estimate for ESR is shown to increase with increasing SAR and total cation concentration unless the effect of total cation concentration is taken into account. This is an important factor to be considered when high-salt solutions are used to reclaim sodic soils.

Cation Exchange Selectivity Coefficient Values on Smectite and Mixed-Layer Illite/Smectite Minerals

2009 ◽  
Vol 73 (3) ◽  
pp. 928-942 ◽  
Author(s):  
Christophe Tournassat ◽  
Hélène Gailhanou ◽  
Catherine Crouzet ◽  
Gilles Braibant ◽  
Anne Gautier ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Mixed Layer ◽  
Selectivity Coefficient ◽  
Exchange Selectivity

scholarly journals Reclamation of Saline–Sodic Soils with Combined Amendments: Impact on Quinoa Performance and Biological Soil Quality

2018 ◽  
Vol 10 (9) ◽  
pp. 3083 ◽  
Author(s):  
María Alcívar ◽  
Andrés Zurita-Silva ◽  
Marco Sandoval ◽  
Cristina Muñoz ◽  
Mauricio Schoebitz
Keyword(s):  
Root Biomass ◽  
Soil Microbial Biomass ◽  
Seed Quality ◽  
Combined Treatment ◽  
Sodium Adsorption Ratio ◽  
Arid Zones ◽  
Exchangeable Sodium ◽  
Sodic Soils ◽  
Soil Microbial ◽  
The Individual

The objective of this study was to evaluate the individual and synergic effects of the application of Biochar (B), Humic Substances (HS), and Gypsum (G) on the soil properties of a saline–sodic soil, and plant growth and seed quality (polyphenols, protein and yield) of quinoa. Treatments included (B) 22 t ha−1, (HS) 5 kg ha−1, and (G) 47.7 t ha−1. Two quinoa genotypes from Arid Zones (AZ-51 and AZ-103) were selected and established in eight treatments. The B + HS + G combined treatment resulted in increases in root biomass of 206% and 176% in AZ-51 and AZ-103, respectively. Furthermore, electrical conductivity (ECe), sodium adsorption ratio (SAR), and exchangeable sodium percentage (ESP) decreased significantly in all treated soils. When compared to the control, ESP decreased 11-fold in the G treatment, and 9–13-fold in the B + G; B + HS; and B + HS + G treatments. Similarly, soil microbial biomass increased 112% and 322% in the B + HS + G treatment in AZ-51 and AZ-103 genotypes, respectively. Therefore, it can be concluded that the application of combined amendments (B + HS + G) represents an alternative for reclaiming degraded soils, including saline–sodic soils.

The chemistry of saturation extracts of Solonetzic and associated soils

1992 ◽  
Vol 72 (1) ◽  
pp. 43-56 ◽  
Author(s):  
R. J. Heck ◽  
A. R. Mermut
Keyword(s):  
Chemical Evolution ◽  
Soil Development ◽  
Exchangeable Sodium ◽  
Saturation Indices ◽  
Soil Extracts ◽  
Closed Basin ◽  
Cation Concentration ◽  
Exchange Constants ◽  
Salt Affected Soils ◽  
Exchange Selectivity

Cation speciation in soil extracts from a catenary sequence of salt-affected soils was studied to understand the chemical evolution of Solonetzic soils in a closed basin. Major changes in cation speciation were found to occur at each phase of soil development. The proportion of thermodynamically active cations was greater in the extracts from the more leached profiles. Saturation indices suggested that the extracts achieved equilibrium with calcite and gypsum, when present in the soil, within 24 h. Accumulations and/or losses of gypsum and calcite from saline layers indicate that there are ongoing changes in their stability. The ratio of Ca2+/Mg2+ suggested a possible equilibrium with Mg-bearing calcites; conditions existed in certain horizons for the formation of this group of minerals. Correlations between exchangeable sodium ratios and sodium adsorption ratios calculated using cation concentration and activity were similar; however, using activities to determine the exchange constants resulted in significant differences.Key words: Cation speciation, saturation indices, cation adsorption, exchange selectivity constants, Solonetzic soils

The distribution of potassium and sodium between the solution and the solid phase in a ternary (K–Na–Ca) system

Soil Research ◽  
1996 ◽  
Vol 34 (5) ◽  
pp. 749 ◽  
Author(s):  
GJ Levy ◽  
S Feigenbaum
Keyword(s):  
Waste Water ◽  
Solid Phase ◽  
Selectivity Coefficient ◽  
Sodium Adsorption Ratio ◽  
Industrial Processes ◽  
Potassium Salts ◽  
Water Softening ◽  
Selectivity Coefficients

Reduction of sodicity hazards in soils irrigated with waste water can be achieved through the replacement of the Na salts (mainly NaCl), used in water softening and other industrial processes, with potassium salts. We studied the effect of equilibrating a grumusol (Typic Chromoxerert) with solutions of differing potassium adsorption ratio (PAR) and sodium adsorption ratio (SAR), within the range expected in waste water, on the distribution of K and Na between the solution and the solid phase. The K distribution did not depend on the level of Na in the solution, but the distribution of Na between the 2 phases depended strongly on the PAR of the solution. For SAR 10 solutions, ESP decreased from 11.1 to 7.8 as PAR increased from 0 to 4. Gapon selectivity coefficients for Na, calculated separately for each PAR level, also decreased with increasing PAR. The Na distribution between solution and solid phase in a ternary (K–Na–Ca) system could not therefore be predicted from the Gapon selectivity coefficient obtained from a binary (Na–Ca) system.

scholarly journals Greywater treatment by granular filtration system using volcanic tuff and gravel media

2017 ◽  
Vol 75 (10) ◽  
pp. 2331-2341 ◽  
Author(s):  
Abeer Albalawneh ◽  
Tsun-Kuo Chang ◽  
Heba Alshawabkeh
Keyword(s):  
Removal Efficiency ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Sodium Adsorption Ratio ◽  
Biological Oxygen Demand ◽  
Exchangeable Sodium ◽  
Volcanic Tuff ◽  
Arid Conditions ◽  
Filtration System ◽  
Granular Filtration

The main objective of this study was to evaluate the efficiency of a granular filtration system (GFS) in greywater treatment under arid and semi-arid conditions. Six GFSs were designed, constructed, and monitored for approximately 13 months. Each GFS served a single rural Jordanian home by treating their greywater. Volcanic tuff media were used as the filtration media in three of the GFSs while the remaining three GFSs used gravel media. Results show that the biological oxygen demand, chemical oxygen demand, and total suspended solids of the effluent were significantly lower as compared to the influent and demonstrated a removal efficiency of 73%, 65%, and 85%, respectively, when using volcanic tuff media. The removal efficiency was 49%, 51%, and 76%, respectively, when using gravel media. There was a significant increase in the electrical conductivity, pH, potassium (K+), magnesium (Mg2+), chloride (Cl−), sodium (Na+), sulfate (SO42−), bicarbonates (HCO3−), sodium adsorption ratio, and exchangeable sodium percentage in the effluents of the GFS that used volcanic tuff media. The study suggests that GFSs can adequately treat greywater under arid conditions. However, gravel media produce less concentrated effluent compared to the volcanic tuff media.

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