Quantifying the effect of sediment microbial activity in facilitating silica sequestration during early diagenesis (QUALIFIED)

量化早期成岩过程中沉积物微生物活性对促进二氧化硅固存的影响（合格）

• 批准号: 2319429
• 负责人: Jeffrey Krause
• 金额: $ 97.58万
• 依托单位: Marine Environmental Sciences Consortium
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-01-01 至 2026-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2319429&HistoricalAwards=false
• 关键词: Quantifying; effect; sediment; microbial; activity

Reverse weathering is the process that forms clay minerals through reactions that involve biologically produced silica. Carbon dioxide is a byproduct of reverse weathering and an important greenhouse gas. As a result, reverse weathering is considered an important process that has regulated global climate over the earth’s natural history. Prior studies that have examined reverse weathering have focused only on abiotic factors (i.e., factors not affected by biology). This research is the first to examine microbial effects on reverse weathering reactions. The project includes laboratory experiments with well-characterized microbial strains. These experiments will provide understanding of this complicated process in a controlled environment. Follow-up experiments and surveys will be conducted in the northern Gulf of Mexico during two field campaigns led by the scientific team. This project contributes to scientific education and development at many levels. The graduate and postgraduate personnel will learn interdisciplinary approaches and collaborate with an international expert in reverse weathering research. Undergraduate trainees from local community colleges will receive paid internships. The project supports high school education in marine science through a partnership with the Dauphin Island Sea Lab Discovery Hall Program. Scientists involved in this study will also work with a non-profit in Birmingham, Alabama, that brings educational opportunities to underserved and underrepresented students in grades 3-8. Reverse weathering (RW) affects many biogeochemical cycles in the ocean. RW is now recognized to represent ~40% of global oceanic silica burial. Such RW-driven burial restricts movement of dissolved silica back into the water column where it can fuel diatom growth (consuming carbon dioxide) and potentially transport diatom carbon to the deep ocean where it can be sequestered for centuries. RW also is likely to be a major, but poorly understood, sink term in the oceanic cycles of Li, Al, K, Fe, Ge and may play a role in coastal ocean acidification. Preliminary field data from the Mississippi River plume directly demonstrates a role for sediment microbes in the early phases of RW. Given the simplicity in the biological design of these pilot experiments, collaboration between experts in silica cycling and sediment microbiology is necessary to better understand the role of microbes in RW. Through this research, the scientific team will address the general question: What factors determine whether microbes facilitate or impede formation of early diagenetic silica products within the process of RW? This project supports science education across many levels including: (1) programs for K-12 students offered by the Dauphin Island Sea Lab Discovery Hall Program, (2) STEM research experiences for community college students, (3) graduate student and postdoctoral training and (4) international collaboration.This project is funded by the Chemical Oceanography and Biological Oceanography Programs in the Division of Ocean Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

逆风化是通过涉及生物产生的二氧化硅的反应形成粘土矿物的过程，二氧化碳是逆风化的副产品，也是一种重要的温室气体。因此，逆风化被认为是调节地球气候的重要过程。先前研究逆风化的研究仅关注非生物因素（即不受生物学影响的因素）。该研究是第一个研究微生物对逆风化反应的影响的研究。这些实验将在受控环境中提供对这一复杂过程的理解，后续实验和调查将在科学团队领导的两次实地考察中进行。研究生和研究生人员将学习跨学科方法，并与当地社区学院的本科生合作，获得带薪实习机会。与多芬岛海实验室探索大厅计划。参与这项研究的科学家还将与阿拉巴马州伯明翰的一家非营利组织合作，为服务不足和代表性不足的 3-8 年级学生提供教育机会。逆风化 (RW) 会影响海洋中的许多生物地球化学循环。目前，RW 被认为占全球海洋二氧化硅埋藏量的约 40%，这种由 RW 驱动的埋藏限制了溶解的二氧化硅回到水体中，在那里它可以促进硅藻的生长（消耗二氧化碳）并有可能。将硅藻碳输送到深海，在那里它可以被隔离几个世纪，RW也可能是Li、Al、K、Fe、Ge海洋循环中的一个主要但知之甚少的汇项，并且可能在其中发挥作用。密西西比河羽流的初步现场数据直接证明了沉积物微生物在 RW 早期阶段的作用。鉴于这些试点实验的生物学设计简单，二氧化硅循环和沉积物微生物学专家之间的合作是必要的。为了更好地了解微生物在 RW 中的作用，科学团队将解决以下普遍问题：哪些因素决定微生物是否促进或阻碍 RW 过程中早期成岩二氧化硅产物的形成？级别包括：(1) 多芬岛海洋实验室探索馆项目为 K-12 学生提供的项目，(2) 为社区学院学生提供的 STEM 研究经验，(3) 研究生和博士后培训以及 (4) 国际合作。该项目由海洋科学部的化学海洋学和生物海洋学项目资助。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。