Investigating the role and chemical nature of dissolved organic matter in marine environments

研究海洋环境中溶解有机物的作用和化学性质

• 批准号: RGPIN-2019-04947
• 负责人: Reader, Heather
• 金额: $ 1.82万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=680819
• 关键词: Investigating; role; chemical; nature; dissolved

Marine dissolved organic matter (DOM) is an enigmatic pool of carbon-based compounds in the world's oceans, representing a pool of carbon comparable in size to the atmospheric pool of carbon dioxide. It is a complex mixture of thousands of unique chemical compounds, of which only ~10% are truly identifiable. DOM reactivity varies considerably with some fractions turning over in the order of hours to days, and others turning over on the scale of millennia. The chemical nature of DOM drives reactivity and to understand the diverse roles that DOM plays in the carbon cycle from local to global scales, it is necessary to understand the chemistry of DOM. Our research program is defined by the overarching goal of understanding the role that DOM plays in the global carbon cycle and how it impacts marine ecosystems. Three specific objectives will examine different aspects of DOM chemistry: ******1. Linking Reactivity to Detailed Chemical Analysis***Despite recent advances in analytical techniques, little is known about how the presence or absence of individual compounds affects the overall reactivity of DOM. It is this reactivity, however, that determines the ultimate fate of DOM in the marine system. We will use methodical approaches to bridge the structure and function of DOM; focusing on defining the chemical nature of DOM in the context of its reactivity in the marine environment. Specific emphasis will be on determining the important functional groups that drive DOM dynamics.******2. Linking Advanced Analytical Techniques to Optical Properties***Combining optical measurements with detailed chemical analysis will give insight into what causes the optical properties of marine waters, with the goal of developing better chemical tracers for oceanic processes. Advanced analytical techniques will provide the detailed chemical information about DOM, and optical techniques, which are relatively rapid and low-cost, will allow for better spatial and temporal coverage of DOM properties. Developing these linkages will provide better synoptic analyses of the importance of DOM dynamics in marine systems.******3. Investigating the Dynamics of Organic Matter in Sensitive Marine Environments***Marine environments play important roles in the global carbon cycle. With respect to DOM, they are both affected by and affecting how carbon cycles in the marine environment. Understanding DOM cycling in rapidly changing environments is a crucial part of understanding the effects of climate change in the global ocean. Northern and coastal regions are changing rapidly. Our research program will focus on areas such as coastal Labrador and the North Atlantic Ocean. We will investigate DOM dynamics by taking advantage of Volunteer Observing Ships to collect broad spatial and temporal datasets of DOM in the marine environment.******The combination of these three complementary objectives and the results they will provide will help us to understand a challenging but crucial part of the marine carbon cycle.

海洋溶解有机物 (DOM) 是世界海洋中一个神秘的碳基化合物库，其碳库的大小与大气中的二氧化碳库相当。它是数千种独特化合物的复杂混合物，其中只有约 10% 是真正可识别的。 DOM 反应性变化很大，一些部分的转变时间为几小时到几天，而另一些部分的转变时间为数千年。 DOM 的化学性质驱动反应性，为了了解 DOM 在从局部到全球尺度的碳循环中发挥的不同作用，有必要了解 DOM 的化学性质。我们的研究计划的总体目标是了解 DOM 在全球碳循环中发挥的作用以及它如何影响海洋生态系统。三个具体目标将检查 DOM 化学的不同方面： ******1。将反应性与详细的化学分析联系起来***尽管分析技术最近取得了进展，但人们对单个化合物的存在或不存在如何影响 DOM 的整体反应性知之甚少。然而，正是这种反应性决定了 DOM 在海洋系统中的最终命运。我们将使用有条理的方法来连接 DOM 的结构和功能；重点是在海洋环境中的反应性背景下定义 DOM 的化学性质。具体重点将放在确定驱动 DOM 动态的重要功能组上。*****2。将先进的分析技术与光学特性联系起来***将光学测量与详细的化学分析相结合，将深入了解导致海水光学特性的原因，目标是为海洋过程开发更好的化学示踪剂。先进的分析技术将提供有关 DOM 的详细化学信息，而相对快速且低成本的光学技术将能够更好地覆盖 DOM 属性的空间和时间。发展这些联系将为 DOM 动力学在海洋系统中的重要性提供更好的概要分析。******3。研究敏感海洋环境中有机物的动态***海洋环境在全球碳循环中发挥着重要作用。就 DOM 而言，它们既受海洋环境中碳循环的影响，又影响着海洋环境中碳循环的方式。了解快速变化环境中的 DOM 循环是了解气候变化对全球海洋影响的关键部分。北部和沿海地区正在迅速变化。我们的研究计划将重点关注拉布拉多沿海和北大西洋等地区。我们将利用志愿者观测船收集海洋环境中 DOM 的广泛空间和时间数据集来研究 DOM 动态。******这三个互补目标的结合及其提供的结果将帮助我们理解海洋碳循环中具有挑战性但至关重要的一部分。