Methan oxidation in the water column and its role in the carbon budget of the coastal ocean

水体中的甲烷氧化及其在沿海海洋碳预算中的作用

• 批准号: 16707631
• 负责人: Dr. Susan Mau
• 金额: --
• 依托单位: Department of Earth Science
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2005-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/16707631?language=en
• 关键词: Methan; oxidation; water; column; its

The release of large amounts of the greenhouse gas methane from marine gas reservoirs is believed to have advanced warming episodes in Earth¿s history. However, methane emitted at the seafloor is consumed partly in the ocean by microorganisms, reducing the portion reaching the atmosphere. The main purpose of this project is to quantify the fraction of CH4 oxidized in the water column in relation to the amount discharging, dispersed in the water column and escaping into the atmosphere at different seep settings. For that purpose, the proposer will learn the 14C/3H-tracer technique including the synthesis of the tracers at the University of California, Santa Barbara (UCSB), USA, and apply this technique to measure oxidation rates of CH4 in the water column. The acquired technique will be ideally complemented by CH4 concentration analyses in the water column, ocean current measurements, mapping of bubble plumes, and gas analyses at the sea surface. These investigations will be performed at several vent sites situated in the Santa Barbara Basin/Channel of California in close cooperation with the SEEPS project at the UCSB. The area is ideally suited as it is one of the most active areas of natural marine hydrocarbon seepage in the world. The comparison of results from distinct vent sites will provide new insight to the buffer system of the ocean with regard to hydrocarbon seepage. This is of great value for the assessment of the climatological response of a sudden release of CH4 from marine gas resources.

据信，从海洋天然气储层中释放大量温室气甲烷在地球历史上具有先进的变暖发作。然而，在海底发射的甲基烷被微生物部分消耗在海洋中，从而减少了到达大气的部分。该项目的主要目的是量化水柱中CH4氧化物的分数，与排放量相关，分散在水柱中，并在不同的渗水环境下逃入大气中。为此，该提案将学习14C/3H追踪技术，包括在美国加利福尼亚大学圣塔芭芭拉分校（UCSB）的示踪剂合成，并应用此技术来测量水柱中CH4的氧化速率。理想情况下，通过在水柱中进行CH4浓度分析，海洋电流测量，气泡羽和在海面的气体分析中，将完成该技术。这些调查将在位于加利福尼亚州圣塔芭芭拉盆地/海峡的多个通风口进行，与UCSB的Seeps项目密切合作。该地区非常适合，因为它是世界上天然海洋烃渗漏最活跃的地区之一。从不同的排气位点的结果进行比较将为海洋缓冲系统提供新的见解。这对于评估从海洋天然气资源突然释放CH4的气候反应具有很大的价值。