Vertical Fe GoFlo measurements from R/V Tangaroa cruise 61TG_3052 in the Southern Ocean in 1999 (SOIREE project)

SOIREE Vertical Fe GoFlo Data<br><br> During the cruise we had the following three objectives:<br> (1) Undertake continuous sampling of the infused patch for dissolved/total iron<br> (2) Obtain samples from vertical profiles, using Go-Flo bottles, to examine the<br> partitioning between dissolved and particulate iron within the water column, both<br> inside and outside the patch.<br> (3) Undertake measurements to determine iron speciation within the water column.<br> <br> Go-Flo casts were taken both inside and outside the patch during the course<br> of the experiment. Typically, water samples were obtained from four standard<br> depths (20, 40, 60 and 80 m) throughout the water column at each station. Deeper<br> samples (> 80 m) were obtained at some stations to examine the concentration of<br> iron below the mixed layer. Both filtered (0.2 um) and unfiltered samples were<br> collected. These samples will be analysed for Fe and other trace metals (Zn, Cd, Mn, Cu)<br> back in the clean laboratory at the University of Otago.<br> <br> The speciation of iron was measured using competitive ligand exchange cathodic stripping<br> voltammetry (CLE CSV) on samples from 40 m depth from stations both inside and outside the<br> patch. This technique determines the total concentration of iron binding ligands present<br> in the sample and their relative binding strengths. From the data generated an estimation<br> of the inorganic iron concentration, Fe`, can also be made, this value can be used to<br> approximate the amount of iron that may be available for uptake by the phytoplankton.<br> <br> <i><b>References</b><br> Bowie, A.R., Maldonado, M.T., Frew, R.D., Croot P.L., Achterberg, E.A., Mantoura, R.F.C.,<br> Worsfold, P.J., Law, C.S., Boyd P.W., The Fate of Added Iron during a Mesoscale Fertilisation<br> Experiment in the Southern Ocean, Deep-Sea Research II (2001), SOIREE special issue, in the press.<br> <br> Bruland, K.W., Franks, R.P., Knauer, G.A., Martin, J.H., 1979. Sampling and analytical methods for<br> the determination of copper, cadmium, zinc and nickel at the nanogram per litre level in seawater.<br> Analytica Chimica Acta 105, 233-245.<br> <br> Danielsson, L.G., Magnusson, B., Westerlund, S., Zhang, K., 1982. Trace-metal determinations<br> in estuarine waters by electrothermal atomic-absorption spectrometry after extraction of<br> dithiocarbamate complexes into freon. Analytica Chimica Acta 144, 183-188.<br> </i><br>SOIREE航次垂直剖面铁元素Go-Flo采样数据集 本航次设定三项核心研究目标： (1) 对人工投加铁肥的斑块开展溶解态/总铁的连续采样； (2) 采用Go-Flo采水器获取垂直剖面水样，以检测斑块内部及外围水体中溶解态铁与颗粒态铁的分配特征； (3) 开展水体中铁形态的测定工作。 实验期间，在斑块内部及外围均开展了Go-Flo采水站位布设。通常情况下，每个站位会在全水柱的四个标准深度（20、40、60和80米）采集水样；部分站位额外采集了80米以深的水样，以检测混合层下方的铁元素浓度。本次采样同时获取了过滤（0.2微米孔径）与未过滤的水样，所有样品将送往奥塔哥大学的洁净实验室，开展铁及其他痕量金属（锌、镉、锰、铜）的分析检测。 本次研究采用竞争性配体交换阴极溶出伏安法（CLE CSV），对斑块内部及外围站位40米深度的水样进行铁形态测定。该方法可定量水样中所有铁结合配体的总浓度及其相对结合强度；基于所得实验数据，还可估算无机铁浓度（Fe'），该数值可用于近似计算浮游植物可利用的铁元素总量。 参考文献 Bowie, A.R.、Maldonado, M.T.、Frew, R.D.、Croot, P.L.、Achterberg, E.A.、Mantoura, R.F.C.、Worsfold, P.J.、Law, C.S.、Boyd, P.W.，《南大洋中尺度施肥实验中投加铁的归宿》，《深海研究第二辑》（2001年，SOIREE专刊，待刊）。 Bruland, K.W.、Franks, R.P.、Knauer, G.A.、Martin, J.H.，1979。海水中纳克每升级铜、镉、锌和镍的采样与分析方法，《分析化学学报》，105卷，233-245页。 Danielsson, L.G.、Magnusson, B.、Westerlund, S.、Zhang, K.，1982。二硫代氨基甲酸酯络合物萃取-氟利昂富集后电热原子吸收光谱法测定河口水体中的痕量金属，《分析化学学报》，144卷，183-188页。