What is the major constituent of soil?

The major constituent of soil is mineral matter. This refers to the inorganic components that are derived from the weathering of rocks and minerals. Mineral matter includes particles of various sizes, such as sand, silt, and clay, which make up a significant portion of the soil's volume and play a critical role in soil structure, fertility, and drainage.

Mineral matter provides essential nutrients necessary for plant growth and contributes to the physical properties of the soil, such as texture and porosity. Unlike organic matter, which is derived from decomposed plant and animal materials, mineral matter is foundational to the soil matrix and directly influences its capacity to hold water and nutrients.

In contrast, while organic matter, air, and water are important components of soil, they do not make up the majority of its composition. Air consists of the gases in the soil pore spaces, and water is found in the soil solution, both of which contribute to soil health but are present in smaller amounts compared to mineral matter. Organic matter, while vital for soil fertility and microbial life, typically comprises only a fraction of the total soil weight. Therefore, understanding the dominance of mineral matter in soil composition is essential for grasping soil science fundamentals.