The concentration of humic substances and their contribution to iron speciation in waters of the Atlantic sector of the Arctic Ocean and the North Atlantic Ocean@en

In this dataset, we present findings on concentrations (< 0.2 μm) of humic substances, dissolved iron, and humic iron (the fraction of dissolved iron complexed by humic substances) in samples gathered during three distinct cruises across the North Atlantic and Arctic oceans. Our objective was to track the migration of humic substances originating from Siberian river outflows, as they traverse from surface waters of the Arctic Ocean into the North Atlantic Ocean, and to understand their impact on dissolved iron transport in the region. The dataset encompasses results from three cruises: the TransArcII expedition aboard the RV Polarstern (PS94) in the central basins and Atlantic sector of the Arctic Ocean, the GN05 expedition (PS100) in waters of the Fram Strait, and the Metalgate expedition aboard the RV Pelagia (64PE474) in waters surrounding Iceland. Dissolved iron concentrations were determined using ICP-MS (Middag et al. 2023), while humic substances and iron bound to humic substances were measured via Adsorptive Cathodic Stripping Voltammetry following the method outlined by Sukekava et al. (2018). Our findings reveal significant regional variations in the role of humic substances, influencing the prevention of dissolved iron precipitation and facilitating its transport. […]本数据集公开了北大西洋与北冰洋三个独立航次采集的样本中，粒径小于0.2μm的腐殖质（humic substances）、溶解态铁（dissolved iron）以及腐殖质结合铁（humic iron，即由腐殖质络合的溶解态铁组分）的浓度数据。本研究旨在追踪源自西伯利亚河流径流的腐殖质的运移过程——此类腐殖质从北冰洋表层水体向北大西洋迁移，并阐明其对该区域溶解态铁输运过程的影响。本数据集包含三个航次的观测结果：一是在北冰洋中央海盆与大西洋扇区执行的极星号（RV Polarstern）PS94航次TransArcII科考任务；二是在弗拉姆海峡（Fram Strait）海域开展的GN05（PS100）科考任务；三是在冰岛周边海域执行的拉加号（RV Pelagia）64PE474航次Metalgate科考任务。溶解态铁浓度采用电感耦合等离子体质谱仪（ICP-MS）测定（Middag等，2023）；腐殖质及腐殖质结合态铁则依照Sukekava等（2018）提出的方法，通过吸附阴极溶出伏安法（Adsorptive Cathodic Stripping Voltammetry）进行定量分析。本研究结果显示，腐殖质的作用存在显著区域差异：其可抑制溶解态铁的沉淀，并促进其输运。[…]