What is "soil fertility"?

Soil fertility refers specifically to the capacity of soil to provide essential nutrients for plant growth. This concept encompasses the availability of essential nutrients such as nitrogen, phosphorus, potassium, and other micronutrients that plants need to thrive. Fertile soil is characterized by a balanced nutrient profile, which supports healthy root systems, enhances plant growth, increases crop yields, and aids in the overall productivity of agricultural land.

A focus on soil fertility also involves understanding how soil properties, such as its texture, pH, organic matter content, and biological activity, influence nutrient availability and uptake by plants. Efficient soil fertility management practices can lead to improved soil health, better crop performance, and sustainable agricultural practices.

The other options, while related to soil characteristics, do not define soil fertility accurately. For example, the ability of soil to retain water is important for plant health but does not directly address nutrient supply. Similarly, the thickness of the topsoil layer can affect fertility but is not a measure of it, nor does the presence of pollutants in the soil contribute positively to its fertility.