Plant litter

Dead plant material that has fallen to the ground

Plant litter (also leaf litter, tree litter, soil litter, litterfall, or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that has fallen on the top layer of soil, commonly known as the litter layer or O-horizon ("O" for "organic"). Plant litter typically becomes detritus and releases nutrients into the soil when decomposed, and also forms a loose layer of covering that preserves soil moisture, reduces soil erosion and provides concealment for small epigeic and fossorial animals. It is an important factor in ecosystem dynamics, as it is indicative of ecological productivity and may be useful in predicting regional nutrient cycling and soil fertility.

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