Which statement about buffer pH is true?

Which statement about buffer pH is true?

• A. It is a measure of hydrogen ions in a solution and those found on CEC sites of the soil.
• B. It is equal to the soil pH
• C. It is a measure of soil texture
• D. It is unrelated to phosphorus availability

Answer: (A)

Buffer pH captures how much acidity a soil can resist by looking at both the hydrogen ions dissolved in the soil solution and the hydrogen ions that are bound to the soil’s cation exchange capacity. This dual pool governs how pH changes when acids or bases are added: the bound H+ can be released or neutralized, helping keep pH more stable. That makes this statement the best fit because it directly describes the way buffer pH relates to hydrogen ions in solution and on CEC sites. It’s not simply the same as the soil’s pH, it isn’t a measure of soil texture, and while phosphorus availability is influenced by pH, buffer pH isn’t unrelated to the conditions that control P availability.

Buffer pH captures how much acidity a soil can resist by looking at both the hydrogen ions dissolved in the soil solution and the hydrogen ions that are bound to the soil’s cation exchange capacity. This dual pool governs how pH changes when acids or bases are added: the bound H+ can be released or neutralized, helping keep pH more stable. That makes this statement the best fit because it directly describes the way buffer pH relates to hydrogen ions in solution and on CEC sites. It’s not simply the same as the soil’s pH, it isn’t a measure of soil texture, and while phosphorus availability is influenced by pH, buffer pH isn’t unrelated to the conditions that control P availability.