CAREER: The Importance of Iron in the Remineralization of Organic Matter in Estuarine and Continental Shelf Sediments

职业：铁在河口和大陆架沉积物有机物再矿化中的重要性

• 批准号: 0239376
• 负责人: Martial Taillefert
• 金额: $ 49.92万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-03-01 至 2009-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0239376&HistoricalAwards=false
• 关键词: CAREER; Importance; Iron; Remineralization; Organic

ABSTRACTOCE-0239376The fate and transformation of organic carbon in coastal and marine sediments is intrinsic to understanding the carbon cycle and its influences on global climate change. The objective of the proposed research by the PI was to examine the mechanisms of natural organic matter (NOM) transformation in estuarine and continental shelf sediments through in-situ technology and mathematical modeling. The research is based on the following two hypotheses: 1) microbial Fe(III) reduction accounts for a significant portion of NOM remineralization in the target regions, and 2) sufficient oxygen is supplied through bioturbation to recycle Fe(OH)3 efficiently for NOM remineralization. The PI proposed to construct a lander system with a benthic chamber, a micromanipulator and voltammetric microelectrodes to obtain in situ benthic flux data and microprofiles. This in situ data combined with sulfate reduction rates, solid phase and porewater data from sediment cores, and results from reactor experiments would be used to calculate NOM remineralization rates. The PI then proposed to develop a 3-D diagenetic model to predict NOM remineralization in continental shelf and estuarine sediments.Incorporating chemists and engineers into the chemical oceanography field was one of four objectives of the educational component. The PI proposed to involve students in these fields in the development of the lander system and the modeling effort. Additionally, a high school teacher would conduct a research project in the PI's laboratory during the summer as part of an existing program at GIT. The third component entailed development of a laboratory component of an existing Geochemistry course. This laboratory component would include cruises on the R/V Savannah to deploy the lander system and involve the students in the field and laboratory efforts of the proposed research. The fourth component consisted of a student exchange program involving GIT, Skidaway Institute of Oceanography, and European partners.

ABSTRACTOCE-0239376沿海和海洋沉积物中有机碳的命运和转化对于理解碳循环及其对全球气候变化的影响至关重要。 项目负责人拟议研究的目的是通过原位技术和数学模型研究河口和大陆架沉积物中天然有机质（NOM）转化的机制。 该研究基于以下两个假设：1) 微生物 Fe(III) 还原占目标区域 NOM 再矿化的很大一部分，2) 通过生物扰动提供足够的氧气，以有效回收 Fe(OH)3 用于 NOM再矿化。 项目负责人建议建造一个带有海底室、显微操作器和伏安微电极的着陆器系统，以获得原位海底通量数据和微观剖面。 该原位数据与硫酸盐还原率、沉积物岩心的固相和孔隙水数据以及反应堆实验的结果相结合，将用于计算 NOM 再矿化率。 然后，PI 建议开发 3-D 成岩模型来预测大陆架和河口沉积物中的 NOM 再矿化。将化学家和工程师纳入化学海洋学领域是教育部分的四个目标之一。 PI 建议让这些领域的学生参与着陆器系统的开发和建模工作。 此外，作为 GIT 现有项目的一部分，一名高中教师将在暑假期间在 PI 的实验室进行一项研究项目。 第三个部分需要开发现有地球化学课程的实验室部分。 该实验室部分将包括在 R/V Savannah 上巡航以部署着陆器系统，并使学生参与拟议研究的现场和实验室工作。 第四部分包括由 GIT、斯基德威海洋学研究所和欧洲合作伙伴参与的学生交换项目。