The interplay between methanotrophy, methanogenesis, and soil geochemistry and its impact on net methane flux to the atmosphere from Arctic soils

甲烷氧化、甲烷生成和土壤地球化学之间的相互作用及其对北极土壤向大气净甲烷通量的影响

• 批准号: 1261748
• 负责人: Jennifer Roberts
• 金额: $ 5.15万
• 依托单位: University of Kansas Center for Research Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-10-01 至 2014-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1261748&HistoricalAwards=false
• 关键词: interplay; between; methanotrophy; methanogenesis; soil

Abstract(1) Technical descriptionMicrobial communities recycle carbon and nitrogen in the terrestrial environment and are central to the flux of soil gases, including methane (CH4), a potent greenhouse gas. Unfortunately, patterns of CH4 release from soils, especially in the Arctic are changing, and there is an urgent need to better understand the basis of in situ CH4 production by methanogens and oxidation rates and patterns by methanotrophs; the main biological mechanism for CH4 consumption. Laboratory work by the PI has established that mineral-bound nutrients are accessible to methanotrophs and enhance their activity. Preliminary fieldwork in soil environments near Ny Ålesund, Svalbard suggests that soil macronutrients, such as P, and perhaps trace metals like Cu and Ni may limit methanotroph activity and therefore methane oxidation rates. There is little known, however, how these geochemical and nutrient conditions vary through the biological active zone (BAZ) and impact methanogenesis. In collaboration with two researchers from Newcastle University in the UK, who will perform all microbiological, metagenomic and gas flux analyses, the PI proposes to perform geochemical, mineralogical, and isotopic analyses on soils collected through the BAZ from more than 13 sites in the vicinity of Ny Ålesund, Svalbard. EAGER funds are requested to: 1. Field-test these laboratory relationships in a complex natural Arctic permafrost soil environment, in which success is not guaranteed. 2. Test the innovative hypothesis that soil geochemistry is a fundamental control on methane flux, a hypothesis that has not been field-tested previously, nor with the rigor of our proposed sampling plan that includes variation in altitude, hydrology, geomorphology, and bedrock lithology. 3. Develop a geochemical tool for predicting methane flux in Arctic environments, which utilizes existing geochemical data or new data, acquired at relatively low cost. (2) Broader significance and importanceMethane fluxes from Arctic soils are an important input into the global climate system; this project, if successful, can strengthen our ability to predict and model global climate change. Understanding the link between soil geochemistry and methanotroph/methanogen activity has broad applicability for many natural systems outside of the Arctic. This project strengthens international collaboration (with UK researchers). One B.S. student will be trained through this grant. The PI has also partnered with a biology high school teacher to provide research opportunities for high school students.

摘要(1) 技术描述微生物群落在陆地环境中循环利用碳和氮，并且是土壤气体通量的核心，其中包括甲烷（CH4）这种强效温室气体。不幸的是，土壤（尤其是北极地区）的 CH4 释放模式正在发生变化，迫切需要更好地了解甲烷菌原位产生 CH4 的基础以及甲烷氧化菌的氧化速率和模式； CH4 消耗的主要生物机制。 PI 的实验室工作已经证实，甲烷氧化菌可以利用矿物质结合的营养物质并增强其活性。对斯瓦尔巴群岛新奥勒松附近土壤环境的初步实地调查表明，土壤常量营养素（例如磷）以及微量金属（例如铜和镍）可能会限制甲烷氧化菌的活性，从而限制甲烷氧化速率。然而，人们很少知道这些地球化学和营养条件如何通过生物活性区（BAZ）变化并影响产甲烷作用。 PI 与英国纽卡斯尔大学的两名研究人员合作，对通过 BAZ 从斯瓦尔巴群岛新奥勒松附近超过 13 个地点收集的土壤进行地球化学、矿物学和同位素分析，这两名研究人员将进行所有微生物学、宏基因组和气体通量分析。 EAGER 资金用于： 1. 在复杂的北极永久冻土自然环境中对这些实验室关系进行现场测试，但不能保证成功。 2. 测试土壤地球化学是甲烷通量的基本控制这一创新假设，该假设之前尚未经过现场测试，也没有经过我们提出的采样计划的严格性（包括海拔、水文、地貌和基岩岩性的变化）。 3. 开发一种地球化学工具来预测北极环境中的甲烷通量，该工具利用现有的地球化学数据或以相对较低的成本获得的新数据。 (2) 更广泛的意义和重要性 来自北极土壤的甲烷通量是全球气候系统的重要输入；该项目如果成功，可以增强我们预测和模拟全球气候变化的能力。 了解土壤地球化学与甲烷氧化菌/产甲烷菌活动之间的联系对于北极以外的许多自然系统具有广泛的适用性。 该项目加强了国际合作（与英国研究人员）。 一名学士学位学生将通过这笔赠款接受培训。 该 PI 还与一名生物高中老师合作，​​为高中生提供研究机会。