Abstract:Ecological and physiological adaptabilities of earthworms in vermifilter were studied under different hydraulic loading,and physiological indexes of earthworms in different filter conditions were compared with that of artificial cultured earthworm with the same natural influencing factors.The results show that when hydraulic loading rises from 2.4 m3·m-2·d-1 to 6.0 m3·m-2·d-1,density and biomass in unit area of earthworms are affected by hydraulic loading slightly.Though,the two items take on a trend of slowly decrease,they can keep a level of 1.5×104·m-2 and 3 kg·m-2 separately and the filter’s environment is favorable for earthworms to breed and hatch.While compared with artificial cultured earthworms,food taken,digestion,excretion and other ecological functions are brought to excellent play in the case of this loading.What’s more,the digestibility reaches to 35.31%~41.47% which is markedly prior to that (17.17%~25.95%)of earthworms in cow dung.However,when the hydraulic loading increases up to 6.7 m3·m-2·d-1,earthworm number and bio quantity reduces 1/3 and respiratory system function has a notable decrease which is notably lower than that of artificial cultured earthworms,furthermore, metabolism level of sludge is influenced.In order to maintain a good living environment for earthworms to assure the exertion of ecological function,it is commended that the running hydraulic loading in earthworm vermifilter should not exceed 6.7 m3·m-2·d-1.
