Why biological activity is one of the factors of soil formation?

Biological activity is a key factor in soil formation because organisms such as plants, animals, and microorganisms contribute to the breakdown of organic matter, enriching the soil with nutrients. This decomposition process leads to the creation of humus, enhancing soil structure and fertility. Additionally, roots of plants help in soil aeration and stabilization, while organisms like earthworms facilitate soil mixing and nutrient cycling. Overall, biological activity promotes the development of a diverse and productive soil ecosystem.