ERIC Number: EJ1474923
Record Type: Journal
Publication Date: 2025-Jun
Pages: 6
Abstractor: As Provided
ISBN: N/A
ISSN: ISSN-2168-8273
EISSN: EISSN-2168-8281
Available Date: 2025-05-06
Soil Cation Exchange Capacity: A New Method for Soil Science Laboratories
Natural Sciences Education, v54 n1 e70014 2025
Determining cation exchange capacity (CEC) is a foundational procedure in soil science education. Traditional introductory soil science CEC laboratory methods, both qualitative and quantitative, vary in complexity, resource requirements, and time constraints. Qualitative methods often rely on visual indicators such as cloudiness in solutions or the interaction with organic dyes, while quantitative methods, including titration endpoints and cation replacement, and may require precise analytical instrumentation. The objective of this study was to develop a time-efficient, quantitative CEC determination method that aligns with the constraints of a 2-h soil science laboratory. The electrical conductivity (EC) probe method proposed here was tested using soils from the North American Proficiency Testing program. Solutions of 0.05 M Ca-acetate and 0.05 M Na-oxalate produced a stronger correlation with CEC values (r[superscript 2] = 0.88) than the comparison between direct and summation methods (r[superscript 2] = 0.74). Also, the influence of soluble salts within soil samples did not interfere with the EC method. This method allows for quantitative determination of soil CEC with minimal investment, and provides reliable results for instructors and students.
Descriptors: Soil Science, Laboratories, Introductory Courses, Organic Chemistry, Testing, Laboratory Equipment, Laboratory Procedures
Wiley. Available from: John Wiley & Sons, Inc. 111 River Street, Hoboken, NJ 07030. Tel: 800-835-6770; e-mail: cs-journals@wiley.com; Web site: https://www.wiley.com/en-us
Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A
Author Affiliations: 1School of Natural Resource Sciences, North Dakota State University, Fargo, North Dakota, USA