Question

What provide humus to the soil

Answer 1

The dark-colored, formless material that typically coats mineral particles in the topsoil. It’s created by the digestion and decay of organic matter. This process is one of repeated feeding by worms and arthropods, bacteria, archaea, and fungi. Eventually that dead leaf, twig, or flake of bark becomes a black goo remaining from the original organic matter or generated during the process of feeding by soil biota. Decomposition doesn’t stop there, but continues until its been broken down into its inorganic constituents: carbon dioxide, water, and minerals. That’s why, if you want to maintain organic matter levels in your soil, you have to keep adding organic matter.