HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Oster, J. D. Articles by Shainberg, I. Search for Related Content PubMed Articles by Oster, J. D. Articles by Shainberg, I. Agricola Articles by Oster, J. D. Articles by Shainberg, I.

Exchangeable Cation Hydrolysis and Soil Weathering as Affected by Exchangeable Sodium¹

ABSTRACT

The specific conductance and chemical composition of aqueous soil suspensions were measured as a function of time on suspensions prepared from three arid soils pretreated with acidified salt solutions to remove lime. The release of Ca²⁺, Mg²⁺, and K⁺ from silicate minerals and the hydrolysis of exchangeable Na⁺ occurred rapidly and prevented the preparation of homoionic Na soils. Crystalline ion release and hydrolysis of exchangeable Na⁺ and Ca²⁺ continued after the soils were suspended in distilled water. The rate was enhanced by increasing exchangeable NA⁺. The combination of Ca²⁺ hydrolysis and its release from silicate minerals was sufficient, when coupled with Na⁺ hydrolysis, to cause the solution phase of the suspension to be supersaturated with lime for one soil.

Separate experiments with untreated soil and its silt fraction indicated that silt weathers rapidly and contributes significantly to the increase in soil conductance. Silt weathering was enhanced by increasing exchangeable Na⁺.

¹ Contribution from U. S. Salinity Laboratory, USDA, Riverside, CA 92501, and Agricultural Research Organization. The Volcani Center, Bet Dagan, Israel. Financial support by the ARO of the senior author is gratefully acknowledged.

² Soil Scientists, U. S. Salinity Laboratory, and Physical Chemist, The Volcani Center, respectively.

Received for publication May 8, 1978. Accepted for publication September 26, 1978.