Effect On Growth And Fecundity Of Earthworms By Controlling C/N With Different Means In Organic Material

Dealing with the organic waste is the main point in the agricultural industry. As an efficient mean,dealing with the waste by earthworms has a broad application prospect. Due to the growth and fecundity of earthworms, which play an important role in this mean,the properties of organic waste that affect earthworms should be focus on. It is necessary to discuss the possibility making sure that earthworms growing well by controlling properties of organic waste. In this study,the mushroom residue was used to breed earthworms Eisenia foetidain room under lad condition. Adding cow dung and urea were the mean that controlled C/N of mushroom residue. There were nine treatments in the study. The treatments included:(1)puremushroom residue(C/N=25.31);(2)mushroom residue with 12.5%cow dung(C/N=23.33);(3)mushroom residue with 25.0%cow dung(C/N=19.52);(4)mushroom residue with 50.0%cow dung(C/N=18.83);(5)100%cow dung(C/N=14.89);(6)mushroom residue with 1.39 g urea(C/N=23.33);(7)mushroom residue with 4.83 g urea(C/N=19.52);(8)mushroom residue with 5.61 g urea(C/N=18.83);(9)mushroom residue with 11.39 g urea(C/N=14.89). These treatments were used to observe the situation about the growth and fecundity of earthwormsunder different controlling means of C/N. In the same time,the change of the mushroom residueproperties after breeding earthworms were analyzedin attempt to find out the causation that affected the earthworms. The study results we got were expected to provide scientific basis for the application of breeding earthworms with organic waste. The resultswere as following:(1)Earthworms grew normally in all treatments in the early stage in our study. Between 20 days and 40 days,the biomass of earthwormsunder the treatments of C/N in 25.31,23.33,19.52 significantly were higher thanother treatments. The result in organic controlling treatments were better than inorganic treatments,especially inmushroom residue with 25.0%cow dung(C/N=19.52),the total weight of earthworm hasincreased of earthworm 95.6%. The earthworms grew more stably in the late stage.(2)In 40-60 days, the results of fecundity were the best. With the C/N increased, the earthwormshave better fecundity. Earthworms laid more eggs the treatments with high C/N. The reproduction period of earthworms in inorganic treatments delayed about 20 dayscompared to the organic treatments. Theearthworm reproduction result under organic treatments were better. Theorganic controlling treatments of C/N in 19.52 and 23.33 had better effect in fecundity.(3)After breeding earthworms,some properties of the organic waste changed significantly. The content of organic matter and microbial carbon significantly lower than those before occluding earthworms. In the same time,the content of ammonium nitrogen and nitrate nitrogen significantly increased. The causes that making the differences between organic controlling treatments and inorganic treatments were the content of total nitrogen,total phosphorus,DOC,microbial carbon and ammonium nitrogen. Among these properties, the content of carbon and nitrogen made largest impact to the differences between organic controlling treatments and inorganiccontrolling treatments.