Nano-magnetite accelerates 'electron-driven methane production' process
Impact of Nitrogen Deposition on Methane Emission from Coastal Wetlands in the Yellow River
As a greenhouse gas, methane has a higher warming potential than carbon dioxide and plays a crucial role in the global carbon cycle and global climate change. Methane produced by natural activities has a considerable amount (about 250 million tons per year ), Wetland is its largest natural source.Many environmental factors can affect the methane emissions from wetlands, including conductive minerals (such as magnetite and other iron-bearing minerals) widely existing in nature and increased nitrogen deposition due to human intervention Are two important potential factors.
Recently, the team of Electro-microbial Resources and Microbial Ecology and Health, Yantai Institute of Coastal Research, Chinese Academy of Sciences, conducted a study on the influence and mechanism of nano-magnetite on methane production in the Yellow River Delta wetlands. In order to simulate the natural in situ environment more accurately, Different carbon sources, the results showed that the nano-magnetite can significantly improve the methane production rate at the 'hour' level.With natural abundance carbon isotope fractionation and carbon 13 Tracing shows that the increase of methane output is mainly related to the acceleration of carbon dioxide reduction. Researchers using thermodynamics, electrochemistry and model analysis found that methane mainly came from 'electron-driven carbon dioxide reduction', which is a new methane production pathway .High-throughput sequencing analysis based on RNA levels showed that the bacteria with the ability to transmit electrons to the outside of the cell, Geobacter, and methanosarcina, a methane-producing methanotroph, can catalyze methane through the coupling of acetic acid oxidation and electron reduction of carbon dioxide The study analyzed conductive mineral pairs Methane impact pathways, providing new understanding of methane to further understand the wetland conductive mineral participate in emissions.
In addition, the team cooperated with Han Guangxuan's team at the Coastal Wetland Experimental Station of the Yellow River Delta in the Chinese Academy of Sciences to simulate the nitrogen deposition process for four consecutive years (2012 to 2016). The effects of increased atmospheric nitrogen deposition and intermittent flooding on the coastal wetland methane The research shows that ammonium nitrogen increases methane emission in the whole year.The nitrate nitrogen has a little effect on the emission of methane during the flooding period, The archaeal community structure shows that ammonium nitrogen treatment increases Methanocellaceae abundance, which may be an important reason for the increase of methane flux, which helps to recognize the response mechanism of methane emission in coastal wetlands to increased nitrogen deposition and intermittent flooding It provides theoretical support for accurately predicting the source intensity of methane in the coastal wetland under the condition of increased nitrogen deposition.
Relevant research results have been published in Environmental Science: Nano and Science of The Total Environment. The research has been funded by the National Natural Science Foundation of China, the Chinese Academy of Sciences's Hundred Talents Program, Shandong Provincial Natural Science Outstanding Youth Fund and the Taishan Scholar Program for Young Professionals.
