Measuring method of soil cation exchange capacity using Methylene Blue indicator

摘要

PURPOSE: A cation exchange capacity measurement method for soil by using a methylene blue indicator is provided to measure the cation exchange capacity in a site in a short time without using any expensive equipments. CONSTITUTION: In a cation exchange capacity measurement method for soil by using a methylene blue indicator, a methylene blue solution is reacted with the soil and the change of the chromaticity of the reaction solution is measured by a spectrophotometer, wherein the methylene blue solution having a concentration of 0.01-0.1%(w/v) is saturated with the soil for a reaction time of 0.5-2hours, and the change of the chromaticity of the methylene blue solution is measured at 609nm to induce a relation formula by the comparison with a cation exchange capacity measured by the usual method, thereby converting the chromaticity of the methylene blue solution to a cation exchange capacity.