Dissolved trace metal and macronutrient concentrations from field samples collected during the EXPORTS North Atlantic campaign at the Porcupine Abyssal Plain-Sustained Observatory (PAP-SO) site on board the RRS Discovery (DY131) in May 2021

This dataset includes dissolved trace metal (manganese, iron, cobalt, nickel, copper, cadmium, zinc, lead) and macronutrient (nitrate+nitrite, phosphate, silicic acid, nitrite) concentration data from field samples collected during the EXPORTS North Atlantic campaign at the Porcupine Abyssal Plain-Sustained Observatory (PAP-SO) site on board the RRS Discovery (DY131). These data were primarily collected opportunistically during the course of water collection for incubation experiments (see separate dataset for incubations), and provide field context for the shipboard incubation experiments as well as temporal characterization of a retentive anticyclonic eddy occupied over the course of the cruise.

This research focuses on the vertical export of the carbon associated with a major group of phytoplankton, the diatoms in the North Atlantic near the Porcupine Abyssal Plain. The major objective is to understand how diatom community composition and the prevailing nutrient conditions create taxonomic differences in metabolic state that combine to direct diatom taxa to different carbon export pathways. The focus is on diatoms, given their large contribution to global marine primary productivity and carbon export which translates into a significant contribution to the biogeochemical cycling of carbon (C), nitrogen (N), phosphorus (P), iron (Fe) and silicon (Si). It is hypothesized that the type and degree of diatom physiological stress are vital aspects of ecosystem state that drive export. To test this hypothesis, combined investigator expertise in phytoplankton physiology, genomics, and trace element chemistry is used to assess the rates of nutrient use and the genetic composition and response of diatom communities, with measurements of silicon and iron stress to evaluate stress as a predictor of the path of diatom carbon export. The EXPORTS field campaign in the North Atlantic sampled a retentive eddy over nearly a month in May 2021, which coincided with the decline of the North Atlantic Spring Bloom.

本数据集涵盖了EXPORTS（EXPORTS）北大西洋科考航次中，于船载RRS发现号（RRS Discovery，DY131航次）在波多芬深渊平原持续观测站（Porcupine Abyssal Plain-Sustained Observatory，简称PAP-SO）站点采集的现场样品数据，包含溶解态痕量金属（锰、铁、钴、镍、铜、镉、锌、铅）与大量营养盐（硝态氮+亚硝态氮、磷酸盐、硅酸、亚硝态氮）的浓度信息。这些数据主要为开展培养实验采集水样过程中机会性采集的（培养实验相关数据集详见独立数据集），可为船载培养实验提供现场背景支撑，并表征航次期间驻留的滞留型反气旋涡的时间变化特征。

本研究聚焦北大西洋波多芬深渊平原附近海域中，与主要浮游植物类群——硅藻相关的碳垂直输出过程。核心研究目标为解析硅藻群落组成与主导营养盐环境如何共同塑造不同分类群的代谢状态差异，进而引导不同硅藻分类群走向各异的碳输出路径。之所以聚焦硅藻，是因其对全球海洋初级生产力与碳输出贡献显著，进而对碳（C）、氮（N）、磷（P）、铁（Fe）与硅（Si）的生物地球化学循环具有重要贡献。研究假设，硅藻生理胁迫的类型与程度是驱动碳输出的生态系统状态的关键维度。为验证该假设，研究整合了浮游植物生理学、基因组学与痕量元素化学领域的专家研究经验，以评估营养盐利用速率、硅藻群落的遗传组成与响应特征，并通过硅与铁胁迫的测量，将胁迫程度作为硅藻碳输出路径的预测因子。本次北大西洋EXPORTS野外科考航次于2021年5月对一处滞留型反气旋涡进行了近一个月的采样，该时段恰逢北大西洋春季藻华的消退期。