| Composts were used in the experiment to study the effect of inoculating fast decomposing agent on composting and research on microbial community composition In this experiment,a kind of fast decomposing agent–compound bacteria agent was inoculated on composting, Effects of fast decomposing agent on composting of swine manure and research on microbial community changes by PCR-DGGE were done.1 Compared to the control ,fast decomposing agent speeded up the rate of raising temperature of composting, time coming to 65℃was advanced from 5thd to 3thd, the highest composting temperature increased from 67.3℃to 72.7℃,and temperature above 60℃maintained from 17d to 21d. Inoculating fast decomposing agent, on the one hand, accelerated the decomposition of soluble sugar and faecula during the initial composting(former 5days), the decomposition of soluble sugar increased from 36.7% to 54.2%, and the decomposition of faecula increased from 39.4% to 80.2%, on the other hand, fast decomposing agent prompted the crude fiber to decompose during the high temperature, speeded up the degradation rate of total organic matter, and the total organic matter stability stage was advanced from 30d to 25d, shortened the maturity of compost, finally.2 Effects of compost with fast decomposing agent on microbial community changes were reasearched by PCR-DGGE(1) DNA of bacteria in different periods of compost was extracted,and 16S rDNA V3 district of bacteria was got by PCR amplification. Analysising DGGE dendrogram and diversity of bands, it showed that during the composting period the population of microbes showed a wave-like curve, up -down-up by temperature. Initial composting, the number of DGGE bands was 20.During the high-temperature, a large number of mid-temperature microbes died rapidly, and the new thermophiles haven't produced, leading to DGGE bands decline rapidly and the number of vaccination and control treatments DGGE bands were 16,14 respectively. As the temperature continuing, the thermophiles were emerging, making the number of DGGE bands increased again in late high-temperature and two treatments bands were up to 22,23, respectively. During the late maturity, compost temperature kept stability, the number of DGGE bands of the two treatment was still remaining at a high level, thus DGGE bands of inoculated decreased slightly.(2) Analysising PCR-DGGE DNA profiles, during composting, compost microbial dominant bands changed significantly. Some bands existed in the whole process of composting, some bands appeared in the early high temperature, then gradually disappeared, and some dominant bands only appeared in the maturity and late maturity. It showed that microbial community placed a clear succession.(3) Eight samples PCR-DGGE patterns of two different stages of compost were clustered by Quantity one software The composting process could be divided into three stages, including early high temperature of control, late high temperature of control, early high temperature and late high temperature of inoculation, maturity and late maturity of inoculation and control. In early high temperature microbial community structure changed greatly, the similarity value of early high temperature of control as other stages was the lowest. Into the late high temperature, the compost similarity value was gradually increasing, and in the maturity and late maturity, the community structure was gradually stabilizating; It showed that inoculating fast decomposing agent affected the microbial community structure, especially affected the microbial community structure of the early high temperature.The results showed that fast decomposing agent changed microbial community structure significantly, especially changed the early high temperature of compost,and inoculating fast decomposing agent, on one hand, accelerated the decomposition of soluble sugar and faecula during the initial composting, on the other hand, it prompted the crude fiber to decompose during the high temperature,shortened the maturity of compost, finally.
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