Plan the perfect garden with our interactive tool →

Buffering Capacity of Soils

...
Jupiterimages/Photos.com/Getty Images

In chemistry, buffer capacity is the amount of acid or base a buffered solution can soak up before its pH will start to change significantly. The buffer capacity of a soil is important in determining how its pH will change.

Features

Various minerals in soil help to buffer against changes in pH when an acid or base is added. At high pH, calcium, magnesium and potassium oxides, together with carbonates, help to buffer pH changes; at acidic pH, aluminum oxides and iron hydroxides act as buffering agents; at intermediate pH levels, soil organic matter, mineral weathering and exchange reactions help to buffer the soil.

Function

A higher buffer capacity means that the soil can absorb more acid and/or base without a significant change in pH. In general, clay soils have higher buffer capacity than sandy soils, and a higher organic matter content tends to increase buffering capacity.

Significance

Buffering capacity is important because it helps to stabilize the pH. Changes in pH can affect plants in a variety of ways, especially by diminishing the fraction of nutrients in soil that are available to the plants and increasing uptake of undesirable minerals like aluminum.

Related Articles

What Chemicals Can Affect the Growth of Plants?
What Chemicals Can Affect the Growth of Plants?
Gypsum Vs. Lime for Soil
Gypsum Vs. Lime for Soil
PH Levels of Sand
PH Levels of Sand
Difference Between Lightweight & Heavyweight Concrete
Difference Between Lightweight & Heavyweight Concrete
What Is a Plant Vein?
What Is a Plant Vein?
PH Level of Cow Manure
PH Level of Cow Manure
Nutrient Value of Gypsum Fertilizer
Nutrient Value of Gypsum Fertilizer
Is a Venus Flytrap an Autotroph or Heterotroph?
Is a Venus Flytrap an Autotroph or Heterotroph?
Are Chinese Palm Plants Poisonous to Cats?
Are Chinese Palm Plants Poisonous to Cats?
Acids & Bases in Fertilizers
Acids & Bases in Fertilizers
How to Soften Clay Soil
How to Soften Clay Soil
Are Hibiscus Acid-Loving Plants?
Are Hibiscus Acid-Loving Plants?
Iron in Soils
Iron in Soils
Foxgloves & Acid Soil
Foxgloves & Acid Soil
Garden Guides
×