Why do earthworms climb to the ground after raining or sprinkling water?

A: Tokyo meteorological proverb "Earthworms climb up and rain like hemp". Earthworms come out of the hole-the ground is wet and soft, and earthworms will climb out of the ground, which indicates that it will rain.

Natural terrestrial earthworms generally like to live in moist, loose and organic soil, especially in fertile gardens, vegetable gardens, cultivated land, ditches, rivers, ponds, canals and sewers, garbage dumps and pools near canteens.

Earthworms need good ventilation in order to replenish oxygen and discharge carbon dioxide. Especially sensitive to ammonia, flue gas, etc. When ammonia exceeds 17 parts per million, earthworm mucus secretion will increase and the population will die. The main harmful gases in flue gas are sulfur dioxide, carbon monoxide and methane. When artificially breeding earthworms, in order to keep warm, a stove should be built inside, and the pipeline should not leak smoke.

Although earthworms like humid environment, even many terrestrial earthworms can survive for a long time in a completely submerged environment. But they never choose to live in flooded soil. If the breeding bed is flooded, most earthworms will run away immediately, and those who can't escape will appear edema and decrease their vitality.