Description/methods for parameters measured:
\nC parameters performed by Dr. Wei-Jun Cai\u2019s group for:
\nTA - Open cell Gran titration with semi-automatic\u00a0AS-ALK2 Apollo Scitech titrator;
\npH - glass electrode, NBS buffers;
\nDIC - infrared CO2 analyzer (AS-C3, Apollo Scitech).
\nUse Dickson CRM for calibration. DIC/TA samples were filtered (0.45um) and fixed with 100 ul of saturated mercury bichloride.
\nUse the methods of Gran (1952) and Huang, et al. (2012).
Fe parameters:
\nThe method of Stookey (1972) is used to determine dissolved Fe(II) and on addition if hydroxylamine Fe total. Fe(III) is determined by difference. Modified and calibrated by many including Lewis et al (2007) and MacDonald et al (2014). Typically, triplicate measurements performed.
Dissolved Mn parameters:
\nThe porphyrin spectrophotometric method of Madison et al (2011) measures dissolved Mn(II), Mn(III) bound to weaker ligands and total Mn. Method includes calibration and intercomparison of totals with other instrumentation (ICP, AA).\u00a0 Detection limit is 0.050 micromolar. Detection limit (DL) is 50 micromolar with a 1 cm path length cell.
Modification of Madison for Mn(III) bound to strong ligands by adding a reducing agent to a separate subsample with the porphyrin to obtain total Mn. Mn(III) bound to strong ligand complexes is determined by difference. Typically, triplicate measurements performed. Detection limit is 3.0 nanomolar.
\nMnOx on unfiltered samples:
\nThe leucoberbelein blue method is that of Altmann (1972) and Krumblein and Altmann (1973) in 1 cm cells, but can be modified for longer path length cells.
S parameters:
\nO2, H2S and polysulfides by the voltammetry method of Luther et al (2008).
\nA flow cell was also used to collect in situ O2 and H2S data as well as some additional samples. Analysis by voltammetry (Luther et al, 2008).
\nSolid and nanoparticulate S8 (Y\u00fccel et al 2010 and Findlay et al 2014).
\nTypically, triplicate measurements performed.\u00a0
Methods papers used in this project:
\nDissolved Mn speciation parameters:
\nMadison, A., B. M. Tebo, G. W. Luther, III. 2011. Simultaneous determination of soluble manganese(III), manganese(II) and total manganese in natural (pore)waters. Talanta 84, 374-381. http://dx.doi.org/10.1016/j.talanta.2011.01.025
Madison, A. S, B. M. Tebo, A. Mucci, B. Sundby and G. W. Luther, III. 2013. Abundant Mn(III) in porewaters is a major component of the sedimentary redox system. Science 341, 875-878.\u00a0 http://dx.doi.org/10.1126/science.1241396
\nOldham, V. O., S. M. Owings, M. Jones, B. M. Tebo and G. W. Luther, III. 2015. Evidence for the presence of strong Mn(III)-binding ligands in the water column of the Chesapeake Bay. Marine Chemistry 171, 58-66. http://dx.doi.org/10.1016/j.marchem.2015.02.008
\nOldham, V. O., A. Mucci, B. M. Tebo and G.W. Luther III. 2017. Soluble Mn(III)-L complexes are ubiquitous in oxygenated waters and stabilized by humic ligands. Geochimica Cosmochimica Acta 199, 238-246. http://dx.doi.org/10.1016/j.gca.2016.11.043
\n[[\u00a0Here, we modified the method of Madison et al. (2011) for water column samples to achieve a detection limit of 3.0 nM (3 times the standard deviation of a blank) by using a 100-cm liquid waveguide capillary cell and the addition of a heating step as well as a strong reducing agent for Mn Speciation [Mn3+ = MnT \u2013 Mn2+]. See Table 1 in this paper for recovery tests. As weak Mn(III)-L complexes could not be measured in our previous work (Oldham et al, 2015; paper above), this method was used throughout this cruise. ]]
MnOX solids:
\nAltmann, H.H., 1972. Bestimmung von inWasser gel\u00f6stem Sauerstoffmit Leukoberbelinblau I. \u00a0Fresenius' Z. Anal. Chem. 6, 97\u201399.
Krumbein, W. E., and H. J. Altmann. 1973. \u2018A New Method for the Detection and Enumeration of Manganese Oxidizing and Reducing Microorganisms\u2019. Helgol\u00e4nder Wissenschaftliche Meeresuntersuchungen 25 (2-3): 347\u201356. doi:10.1007/BF01611203.
\nDissolved Fe speciation parameters:
\nStookey L.L. 1970. Ferrozine- A New Spectrophotometric Reagent for Iron. Anal. Chem. 42, 779-781.
Lewis, B. L., B. T. Glazer, P. J. Montbriand, G. W. Luther, III, D. B. Nuzzio, T. Deering, S. Ma, and S. Theberge. 2007. Short-term and interannual variability of redox-sensitive chemical parameters in hypoxic/anoxic bottom waters of the Chesapeake Bay. Marine Chemistry 105, 296-308.
\nO2 and H2S, polysulfides:
\nLuther, III, G. W., B. T. Glazer, S. Ma, R. E. Trouwborst, T. S. Moore, E. Metzger, C. Kraiya, T. J. Waite, G. Druschel, B. Sundby, M. Taillefert, D. B. Nuzzio, T. M. Shank, B. L. Lewis and P. J. Brendel. 2008. Use of voltammetric solid-state (micro)electrodes for studying biogeochemical processes: laboratory measurements to real time measurements with an in situ electrochemical analyzer (ISEA). Marine Chemistry 108, 221-235. http://dx.doi.org/10.1016/j.marchem.2007.03.002
Luther, G. W., III, and A. S. Madison. 2013. Determination of Dissolved Oxygen, Hydrogen Sulfide, Iron(II), and Manganese(II) in Wetland Pore Waters. In: Methods in Biogeochemistry of Wetlands, R.D. DeLaune, K.R. Reddy, C.J. Richardson, and J.P. Megonigal, editors. SSSA Book Series, no. 10. SSSA, Madison, WI. p. 87-106. http://dx.doi.org/10.2136/sssabookser10.c6
\nS8:
\nY\u00fccel, M., S. K. Konovalov, T. S. Moore, C. P. Janzen and G. W. Luther, III. 2010. Sulfur speciation in the upper Black Sea sediments. Chemical Geology 269, 364-375. http://dx.doi.org/10.1016/j.chemgeo.2009.10.010
pH and inorganic carbon parameters:
\nGran G. 1952. Determination of the equivalence point in potentiometric titrations, Part II. Analyst, 77: 661-671.
Huang W.-J., Wang Y., and Cai W.-J. 2012. Assessment of sample storage techniques for total alkalinity and dissolved inorganic carbon in seawater. Limnology and Oceanography: Methods, 10: 711-717.
CTD data and analyses of bottles from CTD rosette samples collected on cruise HRS1415.
\nField Papers published as a result of this project (methods included):
\nMadison, A. S, B. M. Tebo, A. Mucci, B. Sundby and G. W. Luther, III. 2013. Abundant Mn(III) in porewaters is a major component of the sedimentary redox system. Science 341, 875-878.\u00a0 http://dx.doi.org/10.1126/science.1241396
MacDonald, D. J., A. J. Findlay, S. M. McAllister, J. M. Barnett, P. Hredzak-Showalter, S. T. Krepski, S. G. Cone, J. Scott, S. K. Bennett, C. S. Chan, D. Emerson and G.W. Luther III. 2014. Using in situ voltammetry as a tool to search for iron oxidizing bacteria: from fresh water wetlands to hydrothermal vent sites. Environmental Science: Processes & Impacts 16, 2117-2126. http://dx.DOI.org/10.1039/c4em00073k
\nFindlay, A. J., A. Gartman, D. J. MacDonald, T. E. Hanson, T. J. Shaw and G. W. Luther, III. 2014. Distribution and size fractionation of elemental sulfur in aqueous environments: The Chesapeake Bay and Mid-Atlantic Ridge. Geochimica Cosmochimica Acta 142, 334-348. http://dx.doi.org/10.1016/j.gca.2014.07.032
\nOldham, V. O., S. M. Owings, M. Jones, B. M. Tebo and G. W. Luther, III. 2015. Evidence for the presence of strong Mn(III)-binding ligands in the water column of the Chesapeake Bay. Marine Chemistry 171, 58-66. http://dx.doi.org/10.1016/j.marchem.2015.02.008
\nLuther, G.W. III, A.S. Madison, A. Mucci, B. Sundby and V. E. Oldham. 2015. A kinetic approach to assess the strengths of ligands bound to soluble Mn(III). Marine Chemistry 173, 93-99. http://dx.doi.org/10.1016/j.marchem.2014.09.006
\nFindlay, A. J., A. J. Bennet, T. E. Hanson and G. W. Luther, III. 2015. Light-dependent sulfide oxidation in the anoxic zone of the Chesapeake Bay can be explained by small populations of phototrophic bacteria. Applied and Environmental Microbiology 81(21), 7560-7569. http://dx.doi.org/10.1128/AEM.02062-15
\nFindlay, A. J., A. Gartman, D. J. MacDonald, T. E. Hanson, T. J. Shaw and G. W. Luther, III. 2014. Distribution and size fractionation of elemental sulfur in aqueous environments: The Chesapeake Bay and Mid-Atlantic Ridge. Geochimica Cosmochimica Acta 142, 334-348. http://dx.doi.org/10.1016/j.gca.2014.07.032
\nOldham, V. O., A. Mucci, B. M. Tebo and G.W. Luther III. 2017. Soluble Mn(III)-L complexes are ubiquitous in oxygenated waters and stabilized by humic ligands. Geochimica Cosmochimica Acta 199, 238-246. http://dx.doi.org/10.1016/j.gca.2016.11.043
\nOlson, L. K. A Quinn, M. G. Siebecker, G.W. Luther III, D. Hastings and J. Morford. 2017. Trace metal diagenesis in sulfidic sediments: Insights from Chesapeake Bay. Chemical Geology 452, 47-59. http://dx.doi.org/10.1016/j.chemgeo.2017.01.018
\nOldham, V. O., M. T. Miller, Laramie T. Jensen and G.W. Luther III. 2017. Revisiting Mn and Fe removal in humic rich estuaries. Geochimica Cosmochimica Acta 209, 267-283. http://dx.doi.org/10.1016/j.gca.2017.04.001
\nCai, W.-J, W.-J. Huang, G. Luther, III, D. Pierrot, M. Li, J. Testa, M. Xue, A. Joesoef, R. Mann, J. Brodeur, Y-Y Xu, B. Chen, N. Hussain, G. G. Waldbusser, J. Cornwell, and W. M. Kemp. 2017. Redox reactions and weak buffer capacity lead to acidification in the Chesapeake Bay. Nature Communications 8, Article number: 369. http://dx.doi.org/10.1038/s41467-017-00417-7
\nFindlay, A. J., D. M. Di Toro and G. W. Luther, III. 2017. A model of phototrophic sulfide oxidation in a stratified estuary. Limnology & Oceanography 62, 1853-1867.\u00a0http://dx.doi.org/10.1002/lno.10539
\nOldham, V. O., M. R. Jones, B. M. Tebo and G.W. Luther III. 2017. Oxidative and reductive processes contributing to manganese cycling at oxic-anoxic interfaces. Marine Chemistry, in press.
BCO-DMO Processing:
\n- added columns for cast, station, and description (were contained as headers/rows);
\n- modified parameter names to conform with BCO-DMO naming conventions;
\n- replaced blanks/missing data with \"nd\" (\"no data\");
\n- replaced \"#N/A\" with \"NA\";
\n- replaced \"ND\" (in all caps) with \"not_detected\";
\n- coverted lat and lon from degrees and decimal minutes to decimal degrees;
\n- added date-time in ISO8601 format using original date and time_GMT fields;
\n- 06 Nov 2017: corrected\u00a0station number for cast 6 (change from 6 to 5) per PI.