Repeta_IronLigandConcentrations_KM1709_MESOSCOPE

Samples were collected on the 2017 MESO-SCOPE cruise (KM1709), which characterized an eddy dipole located to the north of Station ALOHA. These samples were collected along the cruise track transecting an eddy dipole to look at how organic speciation of iron changes as the chemical, biological, and physical characteristics change across the dipole. The seawater samples were collected from the trace metal clean (TMC) rosette, filtered through directly off the Niskin bottle into TMC polycarbonate bottles through an AcroPak 1500 Supor Membraine 0.8/0.2um filter in the trace metal van under positive pressure. Filtered seawater was then extracted onto activated solid phase extraction columns, which were frozen and shipped back to WHOI for analysis. At WHOI, the columns were thawed, eluted with methanol, concentrated, and then analyzed on the LC-ICP-MS. A 4-point calibtration curve of model iron ligands was used to calculate the concentration of individual iron ligands.本次研究样本采集自2017年MESO-SCOPE航次（KM1709），该航次对位于阿罗哈站（Station ALOHA）北侧的偶极涡旋（eddy dipole）开展了特征表征。研究人员沿横穿该偶极涡旋的航迹线采集样本，旨在探究铁的有机形态如何随涡旋两侧的化学、生物及物理特征变化而发生改变。海水样本采集自痕量金属洁净（trace metal clean, TMC）型多管采水器架，从尼斯金采水瓶（Niskin bottle）直接取样后，于痕量金属处理舱内通过正压方式，经AcroPak 1500 Supor 0.8/0.2μm滤膜过滤至TMC聚碳酸酯瓶中。过滤后的海水随后被富集于活化固相萃取柱上，随后将萃取柱冷冻并运回伍兹霍尔海洋研究所（Woods Hole Oceanographic Institution, WHOI）进行分析。在该研究所内，研究人员将萃取柱解冻，以甲醇洗脱、浓缩后，采用液相色谱-电感耦合等离子体质谱联用仪（Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry, LC-ICP-MS）完成分析。实验采用4点模型铁配体校准曲线，计算得到各铁配体的浓度。