Bioturbation

Bioturbation is the reworking of soils and sediments by animals or plants.

Its effects include changing the texture of sediments (diagenesis), bioirrigation, and displacement of microorganisms and non-living particles. Common bioturbators include annelids (ringed worms) such as oligochaetes and Spirobranchus giganteus, bivalves like mussels and clams, gastropods, holothurians, or any other infaunal or epifaunal organisms. Faunal activities, such as burrowing, ingestion and defecation of sediment grains, construction and maintenance of galleries, and infilling of abandoned dwellings, all displace sediment grains and mix the sediment matrix.