Soil pH Variation Within a Soil. II. pH Variation in a Neutral and an Alkaline Soil

Abstract

Soil pH variation exists in particles of every kind of soils, including alkaline soil. The objective of this study was to examine soil pH varia-tion in a neutral and an alkaline soil using the column-leaching method. Column-leaching tests were applied to two soils (Callaway and Mount Palomar) at the depths of 0–30 and 30–60 cm. Two replicates were applied to each column-leaching test. Acidification had started in both soils at the depths of 0–30 and 30–60 cm. The pH differentials between the highest pH value and the lowest pH value in leaching fraction in the neutral and the alkaline soils were within one pH unit, and were smaller than those in the acidified soils. This methodology can help understand the soil acidification process and its rate.