Bioturbation is the mixing of (plant) residues into soils and sediments by biotic activity. It is one of the fundamental processes in ecology, as it stimulates decomposition, creates habitats for other (micro)fauna and increases gas- and water flow through the soil.
On the left: Layers of leaves and dirt with no soil fauna. On the right: Earthworms, potworms, collembola, mites and isopods work their way through the system. This bioturbation comparison time lapse was captured over 15 weeks by Wim van Egmond. It’s one in a series of Soil Life in Action videos. Below, organic kitchen waste composts over two weeks:
And in this video, three earthworms species eat the organic matter and mix soil layers, helping decomposition occur over one month:
h/t Far Beyond the Box.