Humus refers to the component in soil (earth) that is?
Humus the other nutrients (nutrient cycle) in the decomposed organic matter are recycled. Depending on the conditions in which the decomposition occurs, a fraction of the organic matter does not mineralize, and instead is transformed by a process called "humification" into concatenations of organic polymers. Because these organic polymers are resistant to the action of microorganisms, they are stable, and constitute "humus". This stability implies that humus integrates into the permanent structure of the soil, thereby improving it. Humification can occur naturally in soil or artificially in the production of compost. Organic matter is humified by a combination of saprotrophic fungi,
Humus Humus In soil science, humus (derived in 1790–1800 from the Latin "humus" for earth, ground) denominates the fraction of soil organic matter that is amorphous and without the "cellular cake structure characteristic of plants, micro-organisms or animals." Humus significantly affects the bulk density of soil and contributes to its retention of moisture and nutrients. In agriculture, "humus" sometimes also is used to describe mature or natural compost extracted from a woodland or other spontaneous source for use as a soil conditioner. It is also used to describe a topsoil horizon that contains organic matter (humus type, humus form, humus profile).