Nitrogen Losses And Inoculation With Heterotrophic Nitrifier During The Compost Of Livestock And Poultry Manure

Intensive, large-scale livestock have been developed on limited acreage. However, large volume of excreta, livestock wastes have resulted in the increases environment pollution. Composting is an effective approach to treat excreta of animal or poultry for recycling, abatement, and harmlessness, but losses of nitrogen by significant due to ammonium volatilization, can lead to new environmental problem such as offensive odor, acid rain et al., and also reduce the value of compost. How to control the losses nitrogen are becoming ever-increasing concern issues.Outdoor pilot scale experiments, lasted for 70 days, at LVFENG organic fertilizerC.LTD., were conducted to investigate the change of pH value, temperature,NH4+-N,NO3--N, ammonia volatile potential and total nitrogen during aerobic co-composting of chicken manure and rice straw. Both mass loss and nitrogen loss were evaluated on the basis of the invariant absolute value of ash content. The numbers variation of ammonifier, nitrifien denitrifier and nitrogen-fixing bacteria were also studied. The results showed ammonia volatileness was an important way of nitrogen loss in the compost of chicken manure. The nitrogen loss rate was the highest during the early 21 days composting and reached above 15% after 70 days composting. Adding 1% rice straw into chicken manure could reduce the nitrogen loss by 2.52 percentage point. Ammoniation was serious and ammonifier was obviously rose at the beginning of composting, Nitrification, denitrification, nitrifier and denitrifier were found, increasing with the time prolonged. Nitrogen-fixing bacteria has not obviously changes with the composting process. The variations of microbial community have the same change tendency as that of NH4+-N, NO3--N during chicken manure composting.Nitrogen changes of solid wastes involved in nitrogen mineralization,ammoniavolatilization, nitrification and denitrification. Adding the nitrifiers to feces of animal and poultry, reduce nitrogen loss through partial NH4+ - N were transformation nitrate or nitrite. 17 compost samples were collected from high temperature composting in order to enrich, isolate and screening autotrophic nitrifieres or heterotrophic nitrifiers ,which were cultured at 55癈.The influence of carbon source, nitrogen source, mine salt, metal ions, pH value, culuture temperature, liquid volume in flask on growth and nitrification were determined in the Aceatamine medium. The result show: our attempts to enrich, isolate thermophilic autotrophilic nitrifiers was turned out negative and unsuccessful. A thermophilic heterotrophic nitrifier strain was obtained named NH921. The NH921 strain was Gram negative, sporulating, rod shaped bacterium and identified belongs to thermophilic Bacillus species. The nitrification of strain was insignificant and also can denitrification.Indoor scale simulated composting experiments, lasted for 16 days, with different 0%,5%,10%,15%,20% inoculum concentration of strain NH921,were carried out to investigate the change of pH value, ammonium, nitrite, nitrate, total nitrogen and the numbers of NH921 strain in order to depend the controlling nitrogen losses . The result show: the quantity of nitrite, nitrate and the numbers NH921 were insignificant. But all the inoculum treatment can reduce nitrogen loss in the simulated composting experiments.The germination percentage and pathogeicity of the NH921 strain on Green vegetable. Pepper, and Tomato were also studied. It indicated that germination percentage of Greengrocery, Pepper, and Tomato make no different with strain NH921 treatment, and no pathogeicity through pot experiment on Pepper, and Tomato were observed.