[Ecological and physiological adaptabilities of earthworm in biofilter under domestication stage]

Ecological and physiological adaptabilities of earthworm in biofilter under domestication stage is presented, as well as related factors. The results show that, due to the coercion of natural and filter environment, the number and biomass of earthworms present a gradual downward trend after added. But once the conditions become appropriate, hatching of larvae could add the number and biomass of earthworm in the filter. With the increase of temperature, circumjacent earthworms gradually move to the water distribution area, 58 days later earthworms distribution become more uniform. Earthworm density and moisture content exist the significant negative correlation. Temperature, precipitation and rainfall don't affect the ecological indicators of earthworms significantly. When temperature is below 15 degrees C, the earthworms' respiratory rate become more sensitive and decline significantly which is not conducive for earthworms treatment of sewage sludge. In a certain range, it's effective for improving the efficiency of sludge treatment to increase the density of earthworms and distribute earthworms evenly.