Titre du document / Document title

Measuring the cation exchange capacity of forest soils

Auteur(s) / Author(s)

SKINNER M. F. ⁽¹⁾ ; ZABOWSKI D. ⁽²⁾ ; HARRISON R. ⁽²⁾ ; LOWE A. ⁽¹⁾ ; XUE D. ⁽²⁾ ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ New Zealand Forest Research Institute, Private Bag 3020, Rotorua, NOUVELLE-ZELANDE
⁽²⁾ College of Forest Resources, Box 352100, University of Washington, Seattle, WA 98195, ETATS-UNIS

Résumé / Abstract

Various methods have been proposed for assessing the cation exchange capacity (CEC) of soils. A pH 7 buffered ammonium acetate solution is the most widely used method but its use for forest soils has been questioned as it may result in an overestimation of CEC in soils with pH dependent charges. The objective of this study was to determine the most appropriate method for measuring the natural CEC of forest soils using variations of 3 common methods. These methods included: (1) pH 7 buffered ammonium acetate (2) unbuffered 1,0, 0.5, and 0. 1 M ammonium chloride, and (3) the compulsive exchange method using the original method and with magnesium chloride. The CEC of three reference materials (kaolinite, vermiculite and humified organic matter) was predetermined and used for comparison. In addition, samples from the major genetic horizons of 8 soils from Washington State, USA, the North Island, New Zealand, and Indonesia were analyzed for CEC. Results showed that the compulsive exchange method resulted in consistently low CEC values, and did not reflect changes in soil organic matter or pH. The pH 7 buffered ammonium acetate resulted in artificially high CECs in soils high in organic matter and low pH, undoubtedly due to increases in pH dependent charges. Although the 0.5 and 0.1 M NH₄Cl would work well for many forest soils, there may be insufficient NH⁺₄ to completely displace all cations and fill all exchange sites in soils with high CEC. The unbuffered 1.0 M NH₄Cl saturation solution is recommended for forest soils.

Revue / Journal Title

Communications in soil science and plant analysis   ISSN 0010-3624   CODEN CSOSA2 

Source / Source

2001, vol. 32, n^o11-12, pp. 1751-1764 (12 ref.)

Langue / Language

Anglais

Editeur / Publisher

Taylor & Francis, Philadelphia, PA, ETATS-UNIS  (1970) (Revue)

Mots-clés anglais / English Keywords

Spodosols ; Alfisols ; Mollisols ; Inceptisols ; Ultisols ; Asia ; Oceania ; Atlantic Ocean Islands ; America ; North America ; United States ; Indonesia ; New Zealand ; Iceland ; Washington ; Ammonium chloride ; Ammonium Acetate ; Organic matter ; pH ; Forest soil ; Buffer solution ; Comparative study ; Cation exchange capacity ; Measurement method ;

Mots-clés français / French Keywords

Xéroll ; Xéralf ; Humod ; Spodosol ; Alfisol ; Mollisol ; Inceptisol ; Ultisol ; Asie ; Océanie ; Iles Atlantiques ; Amérique ; Amérique du Nord ; Etats Unis ; Haploxéroll ; Paléxéralf ; Cryohumod ; Paléhumult ; Hapludult ; Durochrept ; Indonésie ; Nouvelle Zélande ; Islande ; Washington ; Ammonium chlorure ; Ammonium Acétate ; Matière organique ; pH ; Sol forestier ; Solution tampon ; Etude comparative ; Capacité échange cation ; Méthode mesure ;

Mots-clés espagnols / Spanish Keywords

Spodosols ; Alfisols ; Mollisols ; Inceptisols ; Ultisols ; Asia ; Oceania ; Islas Atlántico ; America ; America del norte ; Estados Unidos ; Indonesia ; Nueva Zelandia ; Islandia ; Washingtón ; Amonio cloruro ; Amonio Acetato ; Materia orgánica ; pH ; Suelo forestal ; Solución de amortiguación ; Estudio comparativo ; Capacidad intercambio catión ; Método medida ;

Localisation / Location

INIST-CNRS, Cote INIST : 15396, 35400009984429.0060