Development And Application Of Microbial Agents For Chicken Manure Composting

Chicken manure is a kind of waste produced in animal husbandry.It will pollute the ecological environment if direct discard to the field or long-term stacking storage.Traditional physical and chemical methods not only difficult in practice and energy-wasting but also may cause secondary pollution.How to deal with chicken manure on a large scale with environmental protection and efficiency has become a crucial problem in modern agricultural production.Chicken manure has no heavy metal pollution and the abundance of organic substances,suggests chicken manure is a good raw material for organic fertilization.In this thesis,we applied the microbial treatment method as well as mixed the chicken manure produced in breeding and corn cobs,corn stalks and other agricultural solid production waste to compost and produce organic fertilizer,which can achieve the harmless,resource-based treatment of chicken manure.Based on this,the following work is carried out in this paper.1.Screening of bacterial strains for selection of microbial agentsWe screened a total of 24 strains with higher enzymatic activity,including 15 strains of bacillus,6 strains of yeast and 3 strains of lactobacillus,considering the degradation ability of starch,pectin,cellulose and protein as primary screening conditions.These strains were verified whether there is antagonism between them and investigated whether they can inhibit the growth of harmful bacteria such as Escherichia coli and Staphylococcus aureus.According to all conditions,we chose BYBCG2(Bacillus licheniformis),BYBCG4(B.licheniformis),BYBC03(Bacillus licheniformis),BYBC05(Bacillus megaterium),BYBC12(Bacillus natto),BYBC1-3(Pseudomonas),BYBC08(Bacillus megaterium),BYBC09(Bacillus licheniformis)and BYBCR8(Bacillus cereus)to produce high temperature-resistant and efficient chicken manure maturation agent.2.Optimization of culture medium and culture conditionsThe medium was optimized by single factor experiment,steepest climb experiment and response surface experiment.The optimized medium formula was F42 fructose syrup 18.78g/L,soybean meal powder 19.63 g/L,ammonium chloride 6.15 g/L,dipotassium hydrogen phosphate 6.16 g/L,potassium dihydrogen phosphate 6 g/L and ferrous sulfate 0.1 g/L.The optimal culture conditions were 10%inoculation amount,p H6.5 and fermentation temperature 41℃.The effective number of viable bacteria after fermentation was increased to 3.4×10~8CFU/m L.3.Application of microbial agents in compostingThe liquid decomposed compound microorganism was injected into the mixed chicken manure pile at 1‰-3‰of the mass of the pile.The ambient temperature changed between13℃and 24℃during composting,and it lasted for 22d until the internal temperature of composting did not significantly change.The maximum temperature of the compost can reach 72.8℃on the 5th day,and the pile kept above 60℃for 13 days.The content of organic matter after composting was 73.3%,which was 13.34%lower than before composting.The content of potassium and phosphorus after composting was 2.28%and 1.91%respectively,which increased by 77.9%and 87.3%compared with those before composting.These results indicate that microbial agents could effectively decompose the organic matter and increase the content of nutrients in the compost.4.Species diversity analysis of compostSamples were collected from early composting,high-temperature period,cooling period and late composting period and high-throughput analysis were carried out to obtain the community diversity in four stages of the compost ripening process.Compared with the other three stages,the relative species differences in the early composting period were 0.89,0.89and 0.90,while the species differences between the cooling period and the late composting period were only 0.44.It indicates that the species composition of the compost pile had a great change after the high-temperature period.After the high-temperature period,Flavobacteriaceae and Bacillaceae were less affected by the high-temperature environment,and the relative abundance of species reached 32.73%and 25.01%in the high-temperature period.Oppositely,the relative species abundance of Corynebacteriaceae,Planococcaceae and Moraxellaceae,which were not high-temperature tolerant,decreased from 16%to less than 1%after high temperature.5.Planting effect of bio-organic fertilizer after decayThe indicators of organic fertilizer after microbial agents rotten are better than the requirements of agricultural industry standard of the People’s Republic of China-organic fertilizer(NY525-2012).In planting experiments,the plant growing of the experimental group has better than the control group after applying the rotten organic fertilizer,therefore the decomposed compost can improve the growth and development of plants.