Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Related Publications
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

CTD data and analyses of bottles from CTD rosette samples collected on cruise HRS1415.

Field Papers published as a result of this project (methods included):
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.  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

Findlay, 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

Oldham, 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

Luther, 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

Findlay, 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

Findlay, 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

Oldham, 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

Olson, 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

Oldham, 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

Cai, 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

Findlay, 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. http://dx.doi.org/10.1002/lno.10539

Oldham, 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.

Description/methods for parameters measured:
C parameters performed by Dr. Wei-Jun Cai’s group for:
TA - Open cell Gran titration with semi-automatic AS-ALK2 Apollo Scitech titrator;
pH - glass electrode, NBS buffers;
DIC - infrared CO2 analyzer (AS-C3, Apollo Scitech).
Use Dickson CRM for calibration. DIC/TA samples were filtered (0.45um) and fixed with 100 ul of saturated mercury bichloride.
Use the methods of Gran (1952) and Huang, et al. (2012).

Fe parameters:
The 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:
The 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).  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.

MnOx on unfiltered samples:
The 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:
O2, H2S and polysulfides by the voltammetry method of Luther et al (2008).
A 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).
Solid and nanoparticulate S8 (Yücel et al 2010 and Findlay et al 2014).
Typically, triplicate measurements performed. 

Methods papers used in this project:
Dissolved Mn speciation parameters:
Madison, 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.  http://dx.doi.org/10.1126/science.1241396

Oldham, 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

Oldham, 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
[[ Here, 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 – 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:
Altmann, H.H., 1972. Bestimmung von inWasser gelöstem Sauerstoffmit Leukoberbelinblau I.  Fresenius' Z. Anal. Chem. 6, 97–99.

Krumbein, W. E., and H. J. Altmann. 1973. ‘A New Method for the Detection and Enumeration of Manganese Oxidizing and Reducing Microorganisms’. Helgoländer Wissenschaftliche Meeresuntersuchungen 25 (2-3): 347–56. doi:10.1007/BF01611203.

Dissolved Fe speciation parameters:
Stookey 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.

O2 and H2S, polysulfides:
Luther, 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

S8:
Yücel, 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:
Gran 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.

BCO-DMO Processing:
- added columns for cast, station, and description (were contained as headers/rows);
- modified parameter names to conform with BCO-DMO naming conventions;
- replaced blanks/missing data with "nd" ("no data");
- replaced "#N/A" with "NA";
- replaced "ND" (in all caps) with "not_detected";
- coverted lat and lon from degrees and decimal minutes to decimal degrees;
- added date-time in ISO8601 format using original date and time_GMT fields;
- 06 Nov 2017: corrected station number for cast 6 (change from 6 to 5) per PI.

Description from NSF award abstract:
The research conducted by investigators in the School of Marine Science and Policy at the University of Delaware and within the Department of Environmental and Biomolecular Systems of Oregon Health and Science University will examine the importance of soluble Mn(III) in the biogeochemical cycling of Mn. To date, most studies of Mn in marine environments have not considered Mn(III), the intermediate oxidation state between the soluble reduced state (Mn(II)) and the more insoluble oxidized state (Mn(IV)). The presence and stability of Mn(III) in marine systems, especially those where oxygen levels are reduced, changes the dynamics and stability, solubility and fate and transport of Mn in these locations, and at interfaces between oxic and low oxygen environments. This is not understood at present and the proposed research is poised to provide new information concerning the Mn cycle and is potentially transformative research. The PIs have developed new methods to examine Mn(III) levels in the environment and this capability will bolster the successful accomplishment of the project's goals. The studies will not only focus on understanding the cycling of Mn between its various oxidation states but will determine the concentration and distribution of Mn(III) in stratified coastal ocean waters and in sediment porewaters. The study will also examine the potentially important role of Mn(III) in mediating and influencing the biogeochemical cycling of Mn with that of Fe and S, which are both important components of the major ocean chemical cycles. A better understanding of the biogeochemistry of Mn will inform not only scientists interested in metal cycling in the ocean but also those focused on studies across redox transition zones. The proposed research has an international component and the investigators have developed plans to broadly disseminate their results to students at all levels and to the community. The Principal Investigators have a strong history in education and graduate student and post-doctoral support and mentoring and this will continue under the current grant.