Organic Matter Decomposition in Red Soil as Affected by Earthworms

摘要

The earthworms Pheretima carnosa,Drawida gisti and Eisenia foetida were studied to compare their contributions to the decomposition of various organic materials surface-applied on red soil in a 165-day greenhouse experiment.The native species Pheretima carnosa and Drawida gisti were equally effective in accelerating the decomposition of maize residue,according to fresh body weight,while commercial species Eisenia foetida had no significant influence on dry mass loss of maize residue,Liming with CaCO3 or CaO showed little effect on maize residue breakdown involved by Pheretima carnosa,but it inhibited this process involved by drawida gisti,The capability of Pheretima carnosa to the decompostition of five kinds of organic materials was thoroughly examined.The dry mass losses in worm treatments were in the order of soybean residue>maize residue>pig manure>semi-decayed maize>ryegrass.however,the relative contributions of the earthworm to dry mass loss were in the order of pig manure(89.8%)>semi-decayed maize residue (49.1%)>maize residue(29.4%)>soybean residue(20.9%)>ryegrass residue(16.5%),Pheretima carnosa consumed 20-120mg dry weight of organic material per gram fresh weight of biomass per day.