Which property of soil primarily influences the retention of cations?

The retention of cations in soil is predominantly influenced by cation exchange capacity (CEC). CEC refers to the ability of soil to hold and exchange positively charged ions (cations) such as calcium, magnesium, potassium, and ammonium. A high CEC indicates that the soil can retain more cations, making them available for plant uptake, which is crucial for plant nutrition.

The CEC is influenced by factors like soil texture and organic matter, but it is specifically a measure of the soil's overall ability to bind cations. Soils with a higher proportion of clay particles and organic matter typically exhibit a higher CEC because they have more surface area and negatively charged sites to attract and hold cations. This means that even if the soil texture or organic matter content is considered, CEC is the direct property that specifically quantifies and determines the soil's capacity to retain cations.

Thus, understanding and managing CEC in soil can lead to better agricultural practices and improved soil fertility, making it a fundamental aspect in the study of soil properties related to nutrient retention.