EXCHANGE OF ALKALINE EARTH CATIONS IN SOIL ORGANIC MATTER
- 1 July 1988
- journal article
- research article
- Published by Wolters Kluwer Health in Soil Science
- Vol. 146 (1) , 6-14
- https://doi.org/10.1097/00010694-198807000-00002
Abstract
We conducted batch equilibration ion exchange experiments to determine selectivity of peat for various alkaline earth ions with calcium as the resident cation. Two levels of Ca-neutralized peat (100 and 33%) were prepared from acid-washed samples (CEC=2.72 mol(+) kg-1) by equilibration with equivalent amounts of CO2-free satureated Ca(OH)2. The pH and concentrations of Ca2+ and the exchanging ion were determined at the end of each equilibration period. Both the 100 and 33% Ca-neutralized peat showed the preferential sequence Mg<Sr<Ca<Ba. Considering the Eisenman model, we suggest that this exchange behavior is due to the widely separated fixed carboxylate sites. The formation of (RCOO Me)+ ion pairs is thus suggested to predominate in such systems.This publication has 1 reference indexed in Scilit:
- Methods of Soil AnalysisPublished by Wiley ,1982