Material and microbial changes during corn stalk silage and their effects on methane fermentation

• Published in: Bioresource technology 2016-12, Vol.222, p.89-99
• Main Authors: Zhao, Yubin, Yu, Jiadong, Liu, Jingjing, Yang, HongYan, Gao, Lijuan, Yuan, XuFeng, Cui, Zong-jun, Wang, Xiaofen
• Format: Article
• Language: English
• Subjects: Archaea - physiology; Biofuels; Carbon - metabolism; Fatty Acids, Volatile - metabolism; Fermentation; Methane - biosynthesis; Methane yield; Microbial community; Microbial Consortia - genetics; Real-Time Polymerase Chain Reaction; Silage - analysis; Silage - microbiology; Silage corn stalk; Volatile fatty acids; Zea mays - metabolism; Zea mays - microbiology
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2016.09.113

•The study investigated methane production of corn stalks with silage time.•Material and microbial characters of corn stalk silage was stable after 10days.•Silage can conserve carbon effectively with a 3.77% DM loss.•Methane production loss from corn stalks during silage was 9.22%. Silage efficiency is crucial for corn stalk storage in methane production. This study investigated characteristics of dynamic changes in materials and microbes during the silage process of corn stalks from the initial to stable state. We conducted laboratory-scale study of different silage corn stalks, and optimized silage time (0, 2, 5, 10, 20, and 30days) for methane production and the endogenous microbial community. The volatile fatty acid concentration increased to 3.00g/L on Day 10 from 0.42g/L on Day 0, and the pH remained below 4.20 from 5.80. The lactic acid concentration (44%) on Day 10 lowered the pH and inhibited the methane yield, which gradually decreased from 229mL/g TS at the initial state (Day 0, 2) to 207mL/g TS at the stable state (Day 10, 20, 30). Methanosaeta was the predominant archaea in both fresh and silage stalks; however, richness decreased from 14.11% to 4.75%.