What is organic matter in soil?

Organic matter in soil refers to the components that originate from once-living organisms. This includes the remains of plants and animals, as well as the decomposed substances produced by microbes and other soil fauna. Organic matter plays a crucial role in enhancing soil fertility, structure, and water retention. It provides essential nutrients as it decomposes, improving the overall health of the soil ecosystem. This makes it vital for effective crop growth and sustainable land management.

The other choices involve elements that do not accurately describe organic matter. Substances derived from rocks pertain to inorganic components, while minerals that improve soil structure are not considered organic. Living soil organisms, although essential for soil health, do not constitute organic matter themselves, but rather contribute to its formation and recycling within the soil ecosystem.