What is Cation Exchange Capacity (CEC)?

Cation Exchange Capacity (CEC) refers to the ability of soil to hold onto positively charged ions, known as cations, as well as micronutrients that are essential for plant growth. Soils with a high CEC can retain and supply a greater quantity of nutrients to plants because they can hold more cations, such as calcium, potassium, magnesium, and ammonium, which are vital for various biochemical processes in plants.

This characteristic is crucial for effective nutrient management; it helps in understanding how well a soil can supply nutrients to crops and how efficiently fertilizers can be utilized. Soils with low CEC tend to leach nutrients more quickly, making it difficult for plants to access the nutrients they need.

In contrast, the other choices address different soil properties. The ability of soil to hold water is related to its texture and structure rather than CEC specifically. Soil pH is a measure of acidity or alkalinity and influences nutrient availability, but it is not the same as CEC. Total organic matter plays a significant role in enhancing soil health and fertility but is not directly synonymous with CEC. Understanding CEC is fundamental for effective nutrient management and soil health assessments, making it a key component in agricultural practices.