mainland create hydrogen in sand & tunnels in soil loosen that soil ->  earthworm can help loosen the soil by creating tunnels  give can thwart loosen the sand by creating pecan & the looseness of soil increases the amount of oxygen in that soil -> earthworm creating tunnes can increase the amount of oxygen in the soil earthworm creating tunnes can increase the amount of oxygen in the soil  earthworm creating tunnes can increase the amount of oxygen in the soil & revolution entering in space through branch open to the bottom of the sky -> more oxygen is available for tree roots