Explain leaching, humification and mineralization as the steps of decomposition process.

Answer: Decomposition is the breakdown of complex organic matter (detritus) into simple inorganic substances by decomposers.

1. Leaching: water-soluble inorganic nutrients from the detritus percolate (seep) down into the soil horizons and get precipitated as unavailable salts.
2. Humification: partly decomposed matter forms a dark, amorphous, colloidal substance called humus. Humus is highly resistant to microbial action and decomposes very slowly; it is rich in nutrients and acts as a reservoir of nutrients.
3. Mineralization: humus is further degraded by some microbes and inorganic nutrients such as NH₄⁺, CO₂, water and minerals are released into the soil, where they are again available to plants.