Although mangrove forestscanuptakeatmospheric CO₂ and store carbonas organic matter called “blue carbon”, it is also an important natural sourceofgreenhouse gas methane. Methanogens are major contributors tomethaneand play important roles in the global carbon cycle.However, our understanding of the key microbes and metabolic pathways responsible for methanogenesis under specific substrates in mangrove sediments is still very limited.

On August 22th 2024, Prof. Meng Li's team published a paper entitled "Methylotrophic substrates stimulated higher methane production than competitive substrates in mangrove sediments" in the international journalScience of the Total Environment.This paper compares the stimulating effects of different types of methanogenic substrates on methane emissions from mangrove sediments and their impact on microbial community structure.

This study revealed that the methylotrophic substrates trimethylamine(TMA) and methanethiol(MT) in mangrove sediments are more effective in stimulating methane emissions than traditional competitive substrates inorganic carbon and acetate.In addition, amplicon and metagenomic sequencing analysis showed thatthetotalrelative abundances ofmethanogenesis-related genes werealso highestin TMA and MT treatments.Besides,MethanococcalesandMethanoarcinalesare the most critical methanogensin mangrove sediments.These results will helpadvanceour understanding of the contributions of different methanogenesis pathways and methanogens to methane emissions in mangrove sediments.

Prof. Meng Li is the corresponding author, and the postdoc Dr. Weiling Dongis the first authorin Institute for Advanced Study, Shenzhen University.The work is support by the grants from the National Natural Science Foundation of China and the Guangdong Major Project of Basic and Applied Basic Research.

Link:https://doi.org/10.1016/j.scitotenv.2024.175677

Figure1 The graphical abstract of experimental design and main results.