环境科学与工程学院暨广东省环境污染控制与修复技术重点实验室

报告题目：有机碳的氧化态与微生物产甲烷过程之间的热力学思考
报 告  人：胡瑞文 博士后研究员
                美国劳伦斯伯克利实验室与加州大学伯克利分校
时      间：2024年09月03日（周二）下午15:00-18:00
地      点：东校园环境大楼A206
主      持：王成 副教授
欢迎广大师生参加！

报告人简介：
      胡瑞文，美国劳伦斯伯克利实验室与加州大学伯克利分校联合培养博士后。本人于2022年获得中山大学环境学院环境科学博士学位。目前主要从事环境微生物组学、微生物生态学和生物信息学研究。担任期刊 Frontiers in Microbiology 的客座编辑。相关研究成果以第一作者发表在环境微生物和生态领域高质量期刊 Environmental Science & Technology、Trends in microbiology、Environment International、Functional Ecology、Biology and Fertility of Soils、Science Total of Environment等8篇， 并主持国家自然科学基金青年项目。

报告内容简介：
     Microbial methanogenesis has an important influence on Earth’s changing climate, but the role of organic carbon composition in controlling methane fluxes and carbon-use efficiency in anaerobic microbial ecosystems is not fully characterized. It is proposed that the mineralization of organic carbon sources with a negative nominal oxidation state of carbon (NOSC) is thermodynamically recalcitrant in anaerobic soils. To profile how systematic variations in the oxidation state of organic carbon influence methane fluxes and carbon-use efficiency of methanogenic microbiomes, we prepared long term anaerobic mesocosms from rice field sediment amended with different monomeric carbon sources varying in NOSC. We found that carbon with negative NOSC is slower to be catabolized, but produces more methane and less carbon dioxide per mole of carbon. 16S rRNA amplicon and metagenomic sequencing data showed that negative NOSC carbon also increases the alpha diversity, increases the abundance of syntrophs and methanogens, and enriches for fermentation pathways that generate more organic acids. Our results provide mechanistic insights into how the oxidation state of organic carbon can control methane and carbon dioxide fluxes and alter the carbon flow pathways in methanogenic microbiomes. Also, given the higher greenhouse forcing potential of methane compared to carbon dioxide, our results suggest important trade-offs and risks inherent in strategies aimed at storing carbon in thermodynamically recalcitrant forms.