Tracking the temporal and spatial variability of dissolved organic matter, its diagenetic state and bioavailability during various bloom states in the North Atlantic

北大西洋不同水华状态下溶解有机质的时空变异、成岩状态和生物有效性的追踪。北大西洋浮游植物水华是每年有记录的最显著的生物事件之一。这种水华代表了生物活动的一个热点，在此期间，通过与水华相关的食物网过程产生了大量溶解的有机物。虽然最近的工作已经揭示了北大西洋水华期间溶解有机质的空间分布，但北大西洋水华背景下溶解有机质变异的时间分辨率缺乏。该项目旨在了解北大西洋溶解有机物的时空动态、组成变异性以及控制其积累、持续和输出的机制。该项目将利用美国宇航局最近资助的一个大型实地项目，名为北大西洋气溶胶和海洋生态系统研究（namames），旨在评估北大西洋浮游植物爆发的基本控制因素，其规模和年际变化。这项研究的结果将为北大西洋浮游植物繁殖背景下的碳循环提供一个机制的理解。这项研究将在加州大学进行。圣巴巴拉，一所为西班牙裔服务的机构，将为从小学到研究生的学生提供教育机会。最近对北大西洋溶解有机物的空间分布进行的研究，加上对水团通风率的测量，估计有大量的碳以溶解有机物的形式从表层海洋垂直出口到深海。然而，溶解有机质知识的一个主要空白是缺乏有价值的时间分辨率来研究控制溶解有机质生产、积累或其质量和生物利用度变化的机制，这是由于水华期和浮游植物周期的变化。本研究将研究北大西洋春季浮游植物爆发的四个不同阶段(1)爆发前、混合阶段、2)营养充足、生物量增加阶段、3)营养紧张、生物量减少阶段和4)爆发后分层阶段)，沿重复经向样带研究溶解有机质动态的时空变异。这将通过连接来自自主原位传感器的连续水柱和表层生态系统特性，以及四个26天协调的船舶和空中现场活动的卫星观测来完成。

Tracking the temporal and spatial variability of dissolved organic matter, its diagenetic state and bioavailability during various bloom states in the North AtlanticCraig CarlsonID: 1537943The North Atlantic phytoplankton bloom is among the most conspicuous biological events annually recorded. This bloom represents a hot spot of biological activity during which a significant amount of dissolved organic matter is produced through bloom-associated food web processes. While recent work has shed some light on the spatial distribution of dissolved organic matter during the North Atlantic bloom, temporal resolution of dissolved organic matter variability in the context of the North Atlantic bloom is lacking. This project aims to understand the temporal and spatial dynamics of dissolved organic matter, its compositional variability, as well as the mechanisms that control its accumulation, persistence and export in the North Atlantic. This project will leverage a large, recently funded, NASA field-program called the North Atlantic Aerosols and Marine Ecosystem Study (NAAMES) designed to evaluate the fundamental controls of the north Atlantic phytoplankton bloom initiation, its magnitude and interannual variability. Results from this research will provide a mechanistic understanding of carbon cycling in the context of the North Atlantic phytoplankton bloom. The research will be carried out at the University of California ? Santa Barbara, a Hispanic-serving institution, and will involve educational opportunities for students from elementary through graduate school.Recent work examining the spatial distribution of dissolved organic matter in the North Atlantic coupled to measurements of water mass ventilation rates has estimated that a significant amount of carbon is vertically exported out of the surface ocean to deep waters as dissolved organic matter. However, an overarching gap in dissolved organic matter knowledge is the lack of valuable temporal resolution necessary to investigate the mechanisms that control dissolved organic matter production, accumulation, or its change in quality and bioavailability as a result of changing bloom phases and phytoplankton cycles. This research will examine the temporal and spatial variability of dissolved organic matter dynamics along a repeated meridional transect during four distinct phases associated with the North Atlantic spring phytoplankton bloom including 1) pre-bloom, mixing phase, 2) nutrient-replete, increasing biomass phase, 3) nutrient-stressed decreasing biomass phase, and 4) post bloom stratified phase. This will be accomplished by coupling continuous water column and surface layer ecosystem properties from autonomous in situ sensors, and satellite observations with four 26-day coordinated ship and airborne field campaigns.