Redox dynamics resulting from chemical and physical fluxes in surficial permeable sediments

表面可渗透沉积物中化学和物理通量引起的氧化还原动力学

• 批准号: 1031947
• 负责人: Brian Glazer
• 金额: $ 68.21万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1031947&HistoricalAwards=false
• 关键词: Redox; dynamics; resulting; chemical; physical

The ability to make in situ measurements of analytes on relevant spatial and temporal scales and the need for robust porewater transport characterizations have limited measurements of chemical fluxes within permeable sediments. Two scientists from the University of Hawaii will combine in situ electrochemistry, modeling, traditional geochemistry, and an eddy correlation oxygen flux measuring system to address the biogeochemical fluxes from nearshore permeable sediments. The research will be carried out at the Kilo Nalu Cabled Nearshore Reef Observatory which will provide (1) data acquisition and data dissemination systems; (2) accessible power and high bandwidth communications for in situ instruments; (3) a wide range of physical oceanographic measurements; and (4) Oahu?s south shore has a wide and predictable variety of surface wave conditions and land-based inputs that impact the redox-sensitive biogeochemistry of its permeable sediments. Results from this study will be used to (1) improve our understanding of the interaction between these active, carbon recycling sediments and the overlying water column; (2) examine in detail the temporal and spatial variability of key redox-reactive chemical species; (3) quantify the relative contributions of benthic photosynthesis, sand ripple position, currents and waves, and episodic organic loading events to redox oscillations; and 4) integrate fine-scale chemical measurements with porewater velocity modeling to calculate biogeochemical fluxes.As regards broader impacts, this project will significantly further our knowledge of the solute fluxes across the permeable sediment/seawater interface, as well as improve our understanding of biogeochemical processes within these types of sediments. In addition, this research would make novel in situ sensor technology available to the ocean sciences community. Outreach activities include education of the public via the Bishop Museum and providing information on their research for websites and educational videos displayed in Waikiki hotels. One postdoc, one graduate student and one undergraduate student would be supported and trained as part of this project.

在相关的空间和时间尺度上对分析物进行现场测量的能力以及对强有力的孔隙水传输特性的需要，限制了对可渗透沉积物内化学通量的测量。来自夏威夷大学的两名科学家将结合现场电化学、建模、传统地球化学和涡旋相关氧通量测量系统来研究近岸可渗透沉积物的生物地球化学通量。研究将在基洛纳鲁电缆近岸珊瑚礁观测站进行，该观测站将提供(1)数据采集和数据传播系统；(2)可获得的电力和现场仪器的高带宽通信；(3)广泛的海洋物理测量；(4)瓦胡岛？S南岸具有广泛且可预测的各种面波条件和陆上输入，这些条件和输入将影响其可渗透沉积物的氧化还原敏感生物地球化学。这项研究的结果将被用来(1)加深我们对这些活性碳循环沉积物与上覆水柱之间相互作用的理解；(2)详细研究关键氧化还原反应化学物种的时空变异性；(3)量化底栖光合作用、沙纹位置、水流和波浪以及周期性有机负荷事件对氧化还原振荡的相对贡献；4)将精细化学测量与孔隙水流速模拟相结合来计算生物地球化学通量。就更广泛的影响而言，该项目将大大加深我们对可渗透沉积物/海水界面上的溶质通量的了解，并加深我们对这些类型沉积物中生物地球化学过程的理解。此外，这项研究将为海洋科学界提供新的现场传感器技术。外联活动包括通过主教博物馆对公众进行教育，并为在怀基基酒店展示的网站和教育视频提供关于他们的研究的信息。作为该项目的一部分，一名博士后、一名研究生和一名本科生将得到支持和培训。