# CEC and pH Correlation



## Grizzly Adam (May 5, 2017)

"Soil pH is important for CEC because as pH increases (becomes less acid), the number of negative charges on the colloids increase, thereby increasing CEC."

"CEC has been shown to be proportional to the pH"

Is there a multiplier or some sort of chart that shows how much CEC is affected by various pH levels?


----------



## robjak (Mar 31, 2020)

My CEC did not change when i went from 5.5 to 7. I also have 2 neighbors that i brought their PH from 5.2 to 6.5 with no real change in CEC.


----------



## ScottW (Sep 16, 2019)

I think I recall reading that the amount of organic matter has a big effect on CEC... more OM providing more cation exchange sites.
My last three years of data:
2020 pH 7.2 OM 7.1% CEC 13.8
2021 pH 6.9 OM 7.2% CEC 15.4
2022 pH 6.9 OM 7.1% CEC 14.0
These year to year numbers might all be too close to each other to draw any real conclusions, especially considering any variability on my part when collecting samples.


----------

