Photodegradation of natural organic matter: Implications for dissolved methane cycling in the ocean

天然有机物的光降解：对海洋中溶解甲烷循环的影响

• 批准号: RGPIN-2017-05135
• 负责人: Xie, Huixiang
• 金额: $ 1.6万
• 依托单位: Université du Québec à Rimouski
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=634019
• 关键词: Photodegradation; natural; organic; matter; Implications

Methane (CH4) is the second most potent greenhouse gas in the atmosphere (after carbon dioxide). Aquatic ecosystems, including rivers, lakes, oceans, wetlands, and saltmarshes, provide an important source of atmospheric CH4. It is commonly accepted that CH4 in natural waters almost exclusively originates from methane production by certain bacteria strictly in the absence of oxygen. This long-established belief, however, contradicts the CH4 distribution in the ocean water column where CH4 concentrations are mostly supersaturated and highest in the oxic surface waters. The presence of this CH4 maximum in the surface ocean is called the “oceanic methane paradox (OMP)”.

甲烷(CH4)是大气中第二大温室气体(仅次于二氧化碳)。包括河流、湖泊、海洋、湿地和盐沼在内的水生生态系统是大气CH4的重要来源。人们普遍认为，天然水域中的甲烷几乎完全来自某些细菌在严格无氧的情况下产生的甲烷。然而，这一由来已久的信念与海洋水柱中甲烷的分布相矛盾，在海洋水柱中，甲烷浓度大多是过饱和的，并且在含氧的表层水域中最高。这种甲烷在表层海洋中的最大值被称为“海洋甲烷悖论(OMP)”。