Soils are composed of mineral and organic matter. Weathered rocks provide soil minerals, while organic matter forms from decayed animal and plant residues. An important component of healthy soil, organic matter helps maintain and improve soil’s physical condition. Some of these benefits include increased nutrient and water holding as well as stabilizing structure, which helps soil drainage.
Organic matter is in a constant state of transition, continually breaking down and releasing finer, more decomposed particles. This breakdown is caused by scavengers in the soil (insects, earthworms, bacteria and fungi) as they feed on organic matter. These scavengers also become part of the soil organic matter when they die. As long as there are fresh sources of tissue in the soil, the cycle can continue and organic matter levels will stay constant. However, if fresh material is not added to the soil, organic matter will slowly be lost.
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