Mechanical vacuum extraction vs. batch equilibration for estimation of exchangeable cations

• Published in: Soil Science Society of America journal Vol. 54; no. 2; pp. 381 - 385
• Main Authors: Huntington, Thomas G., Johnson, A. H., Schwartzman, T. N.
• Format: Journal Article
• Language: English
• Published: Madison, WI Soil Science Society of America 01-03-1990
• Subjects: acid soils; Agronomy. Soil science and plant productions; aluminio; aluminium; analisis del suelo; analyse de sol; Biological and medical sciences; calcio; calcium; cation; cationes; cations; echange d' ion; estados del nordeste eua; etats du nord est eu; extraccion; extraction; forest soils; Fundamental and applied biological sciences. Psychology; intercambio ionico; ion exchange; Methods and techniques; north eastern states usa; podzol; podzoles; podzols; sodio; sodium; Soil science; soil testing; sol acide; sol de foret; suelo acido; suelo forestal; Calcium; Acidity; Aluminium; Forest soil; Exchangeable cation; Determination; Measurement method
• DOI: 10.2136/sssaj1990.03615995005400020014x
• EISSN: 1435-0661
• ISSN: 0361-5995

Mechanical vacuum extraction (MVE) was compared with a typical batch extraction involving a shake followed by filtration in a Buchner funnel (SF) for estimation of exchangeable cations in acidic forest soils. Significant (P < 0.01 or < 0.001) differences were observed between methods for Ca, Al, and Na; the MVE method estimated 7% higher Ca, 26% higher Al, and 41% lower Na than the SF method. No significant differences were observed between methods for Mg and K. The relative efficiency of the MVE procedure vs. the SF procedure generally increased with increasing charge density, following the lyotropic series. The SF procedure yielded higher precision for Al estimation; for exchangeable Ca, the precision of estimates was equivalent by the two methods.