Collaborative Research: TRacing the fate of Algal Carbon Export in the Ross Sea (TRACERS)

智力优势：下沉颗粒是生物泵的主要组成部分，它们通常有两种命运：在水柱中矿化和在海底积聚。然而，在碳的垂直下降中隐藏着另一种出口的命运，即下沉的有机质向细悬浮和/或溶解的有机组分的转化。这一过程已被提出，但很少被观察或量化。因此，可以推测，溶解部分在短时间尺度内大部分矿化。然而，全球海洋溶解有机碳调查表明，在高生产力环境下，水体中有机质积累显著。本提案将研究罗斯海出口通量中有机颗粒从下沉阶段到溶解阶段的转变。罗斯海经历了高出口颗粒产量，低溶解有机碳出口和翻转循环，该地区具有可预测的生产和出口事件的连续性。此外，盆地较浅（000米），因此pi将瞄准的产品相对集中。为了解决提出的假设，pi将使用成熟的和新的生化和光学测量出口生产及其命运。这项工作的结果将帮助研究人员关闭罗斯海的碳预算。更广泛的影响：这项研究将支持研究生和本科生，并将为本科生和大学预科学生提供实地研究经验。从科学上讲，这项研究将增加对罗斯海碳汇的了解，并将有助于开发新的工具来识别、量化和追踪碳。这些pi将通过现场的日常报告和由一些pi与科学教育专家和大学生合作开发的教育模块与K-12学生进行交互。一名K-12教育工作者将被包括在研究巡航中。外展将通过COSEE佛罗里达和弗吉尼亚州诺福克的海事中心进行。

Intellectual Merit: Sinking particles are a major element of the biological pump and they are commonly assigned to two fates: mineralization in the water column and accumulation at the seafloor. However, there is another fate of export hidden within the vertical decline of carbon, the transformation of sinking organic matter to fine suspended and/or dissolved organic fractions. This process has been suggested but has rarely been observed or quantified. As a result, it is presumed that the solubilized fraction is largely mineralized over short time scales. However, global ocean surveys of dissolved organic carbon are demonstrating a significant water column accumulation of organic matter under high productivity environments. This proposal will investigate the transformation of organic particles from sinking to solubilized phases of the export flux in the Ross Sea. The Ross Sea experiences high export particle production, low dissolved organic carbon export with overturning circulation, and the area has a predictable succession of production and export events. In addition, the basin is shallow ( 000 m) so the products the PIs will target are relatively concentrated. To address the proposed hypothesis, the PIs will use both well-established and novel biochemical and optical measures of export production and its fate. The outcomes of this work will help researchers close the carbon budget in the Ross Sea.Broader impacts: This research will support graduate and undergraduate students and will provide undergraduates and pre-college students with field-based research experience. Scientifically, this research will increase understanding of carbon sinks in the Ross Sea and will help develop new tools for identifying, quantifying, and tracking that carbon. The PIs will interface with K-12 students through daily reports from the field and through educational modules developed by several of the PIs in collaboration with science education specialists and college students. A K-12 educator will be included on the research cruises. Outreach will be through COSEE Florida and the Maritime Center in Norfolk, VA.