What is the significance of annelids in nature and human life?

Making moves, the worms loosen the soil, promote the penetration of water and air into it, which are necessary for the development of plant roots. The mucus secreted by the worms sticks together the smallest particles of the soil, preventing it from dispersing and eroding. By dragging plant residues into the soil, the worms promote their decomposition, increasing soil fertility. Many animals feed on ringed worms inhabiting the soil: moles, shrews, hedgehogs, frogs, toads, and various types of birds.
Many species of annelids live on the bottom of sea and fresh water bodies. Found in large quantities, they serve as food for many aquatic animals. Passing sludge through their digestive system, annelids free water from excess organic matter and therefore play a significant role in the biological purification of water bodies.
Ringed worms are also used in medicine.