6. When an earthworm is placed in soil, it tries to go under the soil. Why?
Answers
Why are earthworms important for soil?
Earthworms need the food and habitat provided by surface residue, and they eat the fungi that become more common in no-till soils. As earthworm populations increase, they pull more and more residue into their burrows, helping to mix organic matter into the soil, improving soil structure and water infiltration.
As they earthworm into soil, they bring needed oxygen to plant roots. Water chases them through their tunnels and nourishes plants. Earthworm actually help minimize erosion by increasing soil stability. The only thing that does stop them is dry soil.
Earthworms enhance porosity as they move through the soil. Some species make permanent burrows(earthworm) deep into the soil. These burrows can persist long after the inhabitant has died, and can be a major conduit for soil drainage, particularly under heavy rainfall. At the same time, the burrows minimize surface water erosion.