What does cation exchange capacity (CEC) measure in soil?

Cation exchange capacity (CEC) is a crucial soil property that measures the ability of soil to retain cations, which are positively charged ions. This property is essential for understanding how well soil can hold onto nutrients that plants need for growth, such as calcium, magnesium, potassium, and sodium.

Soil particles, particularly clay and organic matter, have sites that can attract and hold onto these positively charged cations. CEC reflects the soil's capacity to store cations and make them available to plants, directly influencing nutrient availability and soil fertility.

When assessing soil health and fertility management strategies, understanding CEC helps agronomists and crop advisors determine how much nutrient input is necessary and how effectively plants can access the nutrients present in the soil. This insight is foundational for developing sustainable agricultural practices.

Other options may relate to important soil concepts, but they do not accurately define CEC. For instance, the ability to retain anions pertains to anion exchange capacity rather than cations, while overall mineral content doesn't convey information regarding nutrient retention or availability. The effectiveness of nutrient uptake is influenced by various factors, including CEC, but it doesn't specifically measure nutrient retention capability in soil.