A comparison of three methods of determining the cation exchange capacity of calcareous soils

Abstract The object of this study was to compare the results obtained with four methods of determination of cation exchange capacity (CEC) and sum of exchangeable cations (Ca, Mg, K) in soils. One of these methods is Kappen’s method and the others methods are based on different extracting reagents: sodium acetate (pH = 8.2), barium chloride and hexaamminecobalt(III) chloride. Values measured with barium ions and hexaamminecobalt(III) ions as index cations are very comparable and these two methods can be considered as equivalent. Kappen’s method gives overestimated results, especially for acid soils reach in organic matter and very calcareous soils. Sodium acetate, buffering the pH of the extracting solution, causes increase of numbers of negatively charged sites and particularly those bonded to organic matter and for this reason values obtained with this method are overestimated. Nevertheless, it is possible to correct this error for a given soil sample by regression equation considering pH of soil, clay and organic carbon content.

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ION EXCHANGE REMOVAL OF CARBONATES FROM SALINE CALCAREOUS SOILS PRIOR TO DETERMINATION OF CATION-EXCHANGE CAPACITY USING 89Sr++

Soil Science ◽

10.1097/00010694-197511000-00005 ◽

1975 ◽

Vol 120 (5) ◽

pp. 349-353 ◽

Cited By ~ 2

Author(s):

S. H. I. ABDEL-AAL ◽

H. BERGSETH

Keyword(s):

Ion Exchange ◽

Cation Exchange ◽

Cation Exchange Capacity ◽

Calcareous Soils ◽

Exchange Capacity

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Effect of CaCO3 Form on Soil Inherent Quality Properties of Calcareous Soils

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1002.459 ◽

2020 ◽

Vol 1002 ◽

pp. 459-467 ◽

Cited By ~ 1

Author(s):

Mustafa Ismail Umer ◽

Shayma Mohammad Rajab ◽

Hajeen Khalil Ismail

Keyword(s):

Cation Exchange ◽

Cation Exchange Capacity ◽

Great Influence ◽

Calcareous Soils ◽

Aggregate Stability ◽

Inverse Correlation ◽

Exchange Capacity ◽

Quality Properties ◽

Soil Cation Exchange Capacity ◽

Inherent Quality

Four soil samples different in there CaCO3 forms contents (total, active and active /total CaCO3) were taken from tillage horizon 0-30 cm depth to study the impacts of CaCO3 form on some soil inherent quality indicators in calcareous soils. Result revealed that the total CaCO3 forms have a great influence on particle size distribution to make it coarser in general comparing with the absence of CaCO3 with soil particles. The increase of active /total (A/T CaCO3%) till 50% has a positive effect on increasing soil electrical conductivity E.C ds.m-1, while increment of A/T CaCO3 over 50% till 70% detrimentally reduced soil E.C ds.m-1 hundred fold. The elevation of (A/T CaCO3%) has inverse correlation with soil cation exchange capacity (CEC Cmole.kg soil). the elevation of (A/T CaCO3%) has inverse correlation with soil cation exchange capacity (CEC Cmole.kg soil) the (A/T CaCO3%) ratio over 56% till 69% significantly improves the mean weight diameter and macro aggregate. In general the optimum total CaCO3 for micro aggregate formation may not exceed 20%. The best Total and (A/T CaCO3%) for better aggregate stability is between 20 to 48% . The proper total calcium carbonate for better total heterotrophic aerobic bacterial activity is around 20% . The best growth of the Azotobacter species which is belonging to non-symbiotic nitrogen fixing bacteria is obtained when total CaCO3 ranges between 10-20% or between 48-56% of (A/T CaCO3%).

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