Double-Buffer Methods Revisited with Focus on Ionic Strength and Soil/Solution Ratio

Abstract

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Development of buffer methods and evaluation of pedotransfer functions to estimate pH buffer capacity of highly weathered soils

“…In addition to this assumption, soil pH was measured in two different solutions (0.01 m CaCl 2 and buffer). It is acknowledged that differences in pH range, valence and ionic strength will cause errors in pHBC estimates (Aitken & Moody, ; Sikora, ) that were evaluated here.…”

Evaluation of nonhazardous lime requirement estimation methods for Oregon soils

“…Lime buffer capacity methods typically require two separate measurements in order to calculate the lime buffer capacity. One method is the Sikora‐2 method (Sikora, 2012), which is calculated based on the measurement of pH KCl and Sikora buffer pH (Sikora, 2012). Another method is the Single Addition of Ca(OH) 2 method (Liu et al., 2005), in which the lime buffer capacity calculation is based on initial pH CaCl2 , and pH CaCl2 after an addition of Ca(OH) 2 .…”