关键词: 厌氧消化, 玫瑰秸秆, 总固体含量, 荧光原位杂交, 微生物群落

Abstract:

To understand the physiochemical properties of anaerobic digestion of rose straw inoculated with livestock manure under different total solid （TS） contents and the dynamic variations of microbial communities involved， methane production and stability of the anaerobic digestion systems were investigated at 3 different TS contents （3%， 5%， 7%） at room temperature and the composition of key microbial groups in these systems were identified using quantitative fluorescence in situ hybridization （FISH）. The results showed that 3%TS treatment had a maximus methane production and a shortest delay period （20 d）. Based on the volatile solid （VS）， its cumulative methane production after 75 d was 262.80 mL·g^-1 VS， being 16.14% and 23.86% higher than that of the 5%TS and 7%TS treatments， respectively. The volatile fatty acids （VFAs） contents produced in the anaerobic digestions with 3%， 5%， and 7%TS contents increased in the early stage of the experiments and then gradually decreased to the end of the experiments. FISH analysis showed that under all TS contents， the Methanosarcinales were the dominant methanogens during the normal gas production period （30~75 d）， accounting for 77.46% of the total methanogens in 5%TS content. The Desulfovibrionales were the dominant bacteria， at the end of the experiments （75 d）， the abundance of Desulfovibrionales decreased by 8.36% and 1.24% with 3% and 5%TS contents respectively but increased by 1.68% with 7%TS content. In summary， 3%TS was the optimal TS content for anaerobic digestion of rose straw， with maximum gas production， shortest delay period， and relatively stable and efficient microbial community composition， which could most effectively improve the anaerobic digestion performance of rose straw.

Key words: anaerobic digestion, rose straw, total solids content, fluorescence in situ hybridization, microbial community