The Cation Exchange Capacities of Alkaline Soils Are Generally Higher

Multiple Choice

The cation exchange capacities of alkaline soils are generally higher than those of acid soils (Vertisols excepted) .Which of the following characteristics of alkaline soils most likely accounts for this high CEC?

A) high humus content
B) high content of hydrous oxides of iron and aluminum
C) high exchangeable calcium
D) high exchangeable sodium content
E) high content of 2:1 type clays