EARTH SCIENCE > LAND SURFACE > SOILS > CATION EXCHANGE CAPACITY
The sum of exchangeable bases plus total soil acidity at a specific pH value
usually 7.0 or 8.0. When acidity is expressed as salt extractable acidity, the
cation exchange capacity (CEC) is called the effective cation exchange
capacity(ECEC) because this is considered to be the CEC of the exchanger at the
native pH value. It is usually expressed in centimoles of charge per kilogram
Jackson, J.A. (1997) Glossary of Geology. 4th ed. Alexandria,
VA:American Geological Institute. 769 p.