Iron Protection, Removal, and Transport along Anoxic Margins and Impacts on the Open Ocean.

在世界海洋的缺氧水域中，氧气被耗尽了。铁通常限制了缺氧沿海水域的初级生产，那里的铁循环很复杂，而且还没有得到很好的理解。在这个项目中，来自加州大学洛杉矶分校（UCLA）的研究人员将研究东热带南太平洋（ETSP）缺氧水域中的铁循环和运输。2013年，美国GEOTRACES号巡洋舰在这个区域进行了许多海洋化学测量。该项目还将研究铁对亚热带太平洋生产力的影响。研究的目的是：(1)铁羽的形成、维持和运输；(2)缺氧铁循环对热带和亚热带太平洋生物地球化学的影响。该项目将提高我们在世界海洋主要区域探测和解释生物地球化学变化的能力。加州大学洛杉矶分校的研究人员将在ETSP的许多物理和化学梯度中研究铁的循环，铁、氧、氮和碳的循环是耦合的。他们将测试底栖沉积物和下沉颗粒中铁释放的重要性。他们还将测试有机物保护水柱中溶解的铁不被移除的想法。最后，他们将测试海洋环流在铁运输和循环中的重要性。这些测试将通过开发和分析一系列模拟来进行，这些模拟使用的是代表重要过程的铁循环的涡流解析模型，并将其与观测结果进行比较。当模型被配置为最好地解释观测结果时，该模型将用于探索铁在大规模初级生产、氧气分布和含氮气体中的重要性。配置的模型将有助于更大的社区更好地研究海洋中的铁循环。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Oxygen is depleted in anoxic waters of the world ocean. Often iron limits primary production along anoxic coastal waters, where iron cycling is complex and not well understood. In this project, researchers from the University of California Los Angeles (UCLA) will investigate iron cycling and transport in the anoxic waters in the Eastern Tropical South Pacific (ETSP). This is an area where many ocean chemistry measurements were made by the 2013 US GEOTRACES cruise. This project will also examine the impacts of iron on the subtropical Pacific productivity. The researchers aim to understand: (1) the formation, maintenance, and transport the iron plume, and (2) the impact of anoxic iron cycling on the biogeochemistry of the tropical and subtropical Pacific Ocean. This project will improve our ability to detect and interpret biogeochemical variations in a major region of the world ocean. Researchers from UCLA will investigate iron cycling across many physical and chemical gradients in the ETSP, where the cycles of iron, oxygen, nitrogen, and carbon are coupled. They will test the importance of Fe release from benthic sediments and sinking particles. They will also test the idea that organic matter protects dissolved iron in the water column from being removed. Finally, they will test the importance of ocean circulation in iron transport and cycle. These tests will be carried out by developing and analyzing a series of simulations with an eddy-resolving model of the iron cycle that represents the important processes and comparing them against observations. When the model is configured to best explain observations, that model will be used to explore the importance of iron in large scale primary production, oxygen distribution, and nitrogen-containing gases. The configured model will be help the larger community better equipped to study iron cycling in the ocean.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.