Originally Posted by Smallaxe
I may have to ignore the rest of this thread if clay colloids do not make CE Sites under the correct circumstances... My point to be made is Creating The CORRECT Circumstances for the clay to be useful as increasing CEC... so if I stop responding it is becuz once again the conversation will not be allowed to go in that direction... sorry...
Clays (layer silicates) primarily have a permanent charge, with exception to kaolinite, and secondarily pH dependent. How are you going to "create the correct circumstances" that will have any impact on this permanent charge? Further colloids, by definition, are classified as having a diameter of 0.1 to 0.001 μm (microns) .... silt is 0.002 to 0.05 mm by definition.
Now the soil minerals we are concerned about with respect to CEC are layer silicates (clays), amorphous silicates, oxides and hydrous oxides and organic materials. As I have already stated, the only way you can reasonably change a given soils CEC (short of complete removal and replacement) is by increasing the SOM.
Do you realize the amount of damage you cause by incorrectly speculating on public forums?