kationcsereképesség

Kationcsereképesség, often translated as cation exchange capacity (CEC), is a measure of the quantity of exchangeable cations that a soil, clay mineral, or other material can adsorb. It is expressed in milliequivalents per 100 grams of soil or other material (meq/100g). This property is crucial for understanding soil fertility and nutrient availability.

Soil particles, particularly clay minerals and organic matter, possess negative electrical charges on their surfaces. These negative charges attract and hold positively charged ions, known as cations. Common soil cations include calcium (Ca²⁺), magnesium (Mg²⁺), potassium (K⁺), and sodium (Na⁺), as well as essential plant nutrients like ammonium (NH₄⁺). Kationcsereképesség quantifies the total number of these exchangeable cation sites available within a given amount of soil.

Soils with higher kationcsereképesség have a greater ability to retain essential nutrient cations and prevent them from being leached away by water. This leads to improved soil fertility and a more stable supply of nutrients for plant growth. Conversely, soils with low kationcsereképesség, such as sandy soils with little clay or organic matter, are more prone to nutrient deficiencies and may require more frequent fertilization. The kationcsereképesség of a soil is influenced by the type and amount of clay minerals present, as well as the concentration of organic matter.