Buffering capacity Buffering capacity is the ability to withstand rapid pH fluctuation. The greater the buffering capacity, the greater the quantity of acid or base which must be incorporated with a material to alter the pH. Soil types having low buffering capacities include sandy soils containing little clay or organic matter. Soils exhibiting a high buffering capacity are usually composed of large quantities of mineral clay and organic matter. Soils with a high buffering capacity necessitate a greater amount of lime to raise the pH than soils with a low buffering capacity. Exchange acidity is a measure of buffering capacity.
Lime migrates slowly through the soil .
Calcium carbonate, the reference standard, has an E.N.V. of 100. If the plow depth is greater or less than 8 inches, first modify the recommended lime rate according to plow depth. In such situations, increase or decrease the lime application rate by 0.12 for each extra inch. The actual amount of lime to apply can be calculated by dividing the recommended lime rate by the E.N.V. of the liming material. Exchange acidity is not usually calculated during soil analysis when initial soil pH exceeds 6.0.