Collaborative Research: Determining Pathways of Diagenetic Sulfurization of Organic Matter Using Compound-Specific Sulfur Isotopic Analysis

合作研究：利用化合物特异性硫同位素分析确定有机质成岩硫化的途径

• 批准号: 1424228
• 负责人: William Gilhooly III
• 金额: $ 10.15万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1424228&HistoricalAwards=false
• 关键词: Collaborative; Research; Determining; Pathways; Diagenetic

Sulfur is an essential element for all living organisms because it plays a critical role in transferring biochemical energy, enzymatic reactions, and protein synthesis. Thus, the biological and geological chemistry of sulfur is of widespread interest in the Earth science community. Organic sulfur deposited in sedimentary environments is of particular interest due to its impact on petroleum formation and refining and its relationship to microbial sedimentary processes, organic carbon accumulation and the overall interpretation of environmental records. This sedimentary organic matter retains the organic and inorganic history of sulfur initially incorporated into organic tissue (primary) or added during chemical reactions occurring in the sediments (secondary). Despite the importance, little is known about organic sulfur in the natural environment in part because there are a wide variety of organic sulfur compounds and a number of different ways these compounds form. In addition, these compounds can be altered after they are deposited in the sediments. The investigators will use the stable isotope composition of organic sulfur to gain insights into these processes and sources of organic sulfur. Recent technological advances have greatly improved the ability to measure sulfur isotope compositions of individual organic sulfur compounds possible with high precision and at natural abundance. This project will use compound-specific sulfur isotope analysis to study the reaction pathways that form organic sulfur in two anoxic (oxygen free) lakes. The sulfur isotope signature of these compounds will be used to infer reaction pathways to increase understanding of the reactions between sulfur and organic matter that occur in sediments. These new advancements in sulfur isotope analysis have tremendous potential for understanding past changes in elemental cycling, metabolic and ecologic changes, as well as changes in past climatic and environmental conditions.Graduate education will be one broader impact of this project, and we will foster this through extensive collaboration and training in the state of the art sulfur isotope analysis. A second important impact of this project will be to develop educational modules about hypoxic (low oxygen) conditions common to northeast Indiana lakes, and Lake Erie, Pennsylvania, in collaboration with the IUPUI Center for Earth and Environmental Sciences (CEES) Discovering the Science of the Environment (DSE) program. DSE is a public outreach program focused on formal and informal delivery of STEM (Science, Technology, Engineering, and Mathematics) education to fourth through ninth grade students. We will translate knowledge learned from studying sulfur cycling in anoxic lakes into material for teaching modules that inform students about the environmental hazards of human-induced hypoxia.

硫是所有生物体必不可少的元素，因为它在传递生化能量、酶促反应和蛋白质合成中起着关键作用。因此，硫的生物和地质化学在地球科学界引起了广泛的兴趣。沉积环境中的有机硫由于其对石油形成和精炼的影响以及与微生物沉积过程、有机碳聚集和环境记录整体解释的关系而受到特别关注。这种沉积有机质保留了硫的有机和无机历史，硫最初被纳入有机组织（初级）或在沉积物中发生的化学反应中添加（次级）。尽管有机硫很重要，但人们对自然环境中的有机硫知之甚少，部分原因是有机硫化合物种类繁多，形成方式也各不相同。此外，这些化合物在沉积在沉积物中后会发生改变。研究人员将利用有机硫的稳定同位素组成来深入了解这些过程和有机硫的来源。最近的技术进步大大提高了测量单个有机硫化合物的硫同位素组成的能力，可能具有高精度和自然丰度。该项目将使用特定化合物硫同位素分析来研究在两个缺氧（无氧）湖泊中形成有机硫的反应途径。这些化合物的硫同位素特征将用于推断反应途径，以增加对沉积物中硫和有机物之间反应的理解。硫同位素分析的这些新进展对于了解过去元素循环、代谢和生态变化以及过去气候和环境条件的变化具有巨大的潜力。研究生教育将是这个项目的一个更广泛的影响，我们将通过广泛的合作和最先进的硫同位素分析的培训来促进这一点。该项目的第二个重要影响将是与IUPUI地球与环境科学中心（CEES）发现环境科学（DSE）项目合作，开发关于印第安纳州东北部湖泊和宾夕法尼亚州伊利湖常见的缺氧（低氧）条件的教育模块。DSE是一项公共推广计划，重点是向四年级到九年级的学生提供正式和非正式的STEM（科学、技术、工程和数学）教育。我们将把从研究缺氧湖泊中硫循环中学到的知识转化为教学模块的材料，让学生了解人为缺氧对环境的危害。