CTD data and analyses of bottles from CTD rosette samples collected on R/V Hugh R. Sharp cruise HRS1415 in August 2014

Website: https://www.bco-dmo.org/dataset/717687
Data Type: Cruise Results
Version: 1
Version Date: 2017-11-06

Project
» The role of soluble Mn(III) in the biogeochemical coupling of the Mn, Fe and sulfur cycles (Soluble ManganeseIII)
ContributorsAffiliationRole
Luther, George W.University of DelawarePrincipal Investigator
Tebo, Bradley M.Oregon Health & Science University (IEH/OHSU)Co-Principal Investigator
Rauch, ShannonWoods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager

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


Coverage

Spatial Extent: N:39.4967 E:-72.7283 S:38.2493 W:-76.4093
Temporal Extent: 2014-08-18 - 2014-08-24

Dataset Description

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.


Methods & Sampling

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.


Data Processing Description

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.


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Data Files

File
RosetteSamples_HRS1415.csv
(Comma Separated Values (.csv), 43.48 KB)
MD5:edc5f5df8851749f25e6f7511bc3be26
Primary data file for dataset ID 717687

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Related Publications

Cai, W.-J., Huang, W.-J., Luther, G. W., Pierrot, D., Li, M., Testa, J., … Kemp, W. M. (2017). Redox reactions and weak buffering capacity lead to acidification in the Chesapeake Bay. Nature Communications, 8(1). doi:10.1038/s41467-017-00417-7
Methods
Findlay, A. J., Bennett, A. J., Hanson, T. E., & Luther, G. W. (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. doi:10.1128/aem.02062-15 https://doi.org/10.1128/AEM.02062-15
Methods
Findlay, A. J., Di Toro, D. M., & Luther, G. W. (2017). A model of phototrophic sulfide oxidation in a stratified estuary. Limnology and Oceanography, 62(5), 1853–1867. doi:10.1002/lno.10539
Methods
Findlay, A. J., Gartman, A., MacDonald, D. J., Hanson, T. E., Shaw, T. J., & Luther, G. W. (2014). Distribution and size fractionation of elemental sulfur in aqueous environments: The Chesapeake Bay and Mid-Atlantic Ridge. Geochimica et Cosmochimica Acta, 142, 334–348. doi:10.1016/j.gca.2014.07.032
Methods
Methods
Krumbein, W. E., & Altmann, H. J. (1973). A new method for the detection and enumeration of manganese oxidizing and reducing microorganisms. Helgoländer Wissenschaftliche Meeresuntersuchungen, 25(2-3), 347–356. doi:10.1007/bf01611203 https://doi.org/10.1007/BF01611203
Methods
Luther, G. W., Glazer, B. T., Ma, S., Trouwborst, R. E., Moore, T. S., Metzger, E., … Brendel, P. J. (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(3-4), 221–235. doi:10.1016/j.marchem.2007.03.002
Methods
Luther, G. W., Madison, A. S., DeLaune, R. D., Reddy, K. R., Richardson, C. J., & Megonigal, J. P. (2013). Determination of Dissolved Oxygen, Hydrogen Sulfide, Iron(II), and Manganese(II) in Wetland Pore Waters. SSSA Book Series. doi:10.2136/sssabookser10.c6
Methods
Luther, G. W., Madison, A. S., Mucci, A., Sundby, B., & Oldham, V. E. (2015). A kinetic approach to assess the strengths of ligands bound to soluble Mn(III). Marine Chemistry, 173, 93–99. doi:10.1016/j.marchem.2014.09.006
Methods
MacDonald, D. J., Findlay, A. J., McAllister, S. M., Barnett, J. M., Hredzak-Showalter, P., Krepski, S. T., … Luther III, G. W. (2014). Using in situ voltammetry as a tool to identify and characterize habitats of iron-oxidizing bacteria: from fresh water wetlands to hydrothermal vent sites. Environ. Sci.: Processes Impacts, 16(9), 2117–2126. doi:10.1039/c4em00073k
Methods
Madison, A. S., Tebo, B. M., & Luther, G. W. (2011). Simultaneous determination of soluble manganese(III), manganese(II) and total manganese in natural (pore)waters. Talanta, 84(2), 374–381. doi:10.1016/j.talanta.2011.01.025
Methods
Madison, A. S., Tebo, B. M., Mucci, A., Sundby, B., & Luther, G. W. (2013). Abundant Porewater Mn(III) Is a Major Component of the Sedimentary Redox System. Science, 341(6148), 875–878. doi:10.1126/science.1241396
Methods
Oldham, V. E., Jones, M. R., Tebo, B. M., & Luther, G. W. (2017). Oxidative and reductive processes contributing to manganese cycling at oxic-anoxic interfaces. Marine Chemistry, 195, 122–128. doi:10.1016/j.marchem.2017.06.002
Methods
Oldham, V. E., Miller, M. T., Jensen, L. T., & Luther, G. W. (2017). Revisiting Mn and Fe removal in humic rich estuaries. Geochimica et Cosmochimica Acta, 209, 267–283. doi:10.1016/j.gca.2017.04.001
Methods
Oldham, V. E., Mucci, A., Tebo, B. M., & Luther, G. W. (2017). Soluble Mn(III)–L complexes are abundant in oxygenated waters and stabilized by humic ligands. Geochimica et Cosmochimica Acta, 199, 238–246. doi:10.1016/j.gca.2016.11.043
Methods
Oldham, V. E., Owings, S. M., Jones, M. R., Tebo, B. M., & Luther, G. W. (2015). Evidence for the presence of strong Mn(III)-binding ligands in the water column of the Chesapeake Bay. Marine Chemistry, 171, 58–66. doi:10.1016/j.marchem.2015.02.008
Methods
Olson, L., Quinn, K. A., Siebecker, M. G., Luther, G. W., Hastings, D., & Morford, J. L. (2017). Trace metal diagenesis in sulfidic sediments: Insights from Chesapeake Bay. Chemical Geology, 452, 47–59. doi:10.1016/j.chemgeo.2017.01.018
Methods
Yücel, M., Konovalov, S. K., Moore, T. S., Janzen, C. P., & Luther, G. W. (2010). Sulfur speciation in the upper Black Sea sediments. Chemical Geology, 269(3-4), 364–375. doi:10.1016/j.chemgeo.2009.10.010
Methods

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Parameters

ParameterDescriptionUnits
CastCast identifier unitless
StationStation identifier unitless
latLatitude; positive values = North decimal degrees
lonLongitude; positive values = East decimal degrees
dateDate of sampling formatted as m/dd/yyyy unitless
DescriptionDescription and/or notes related to the sampling location or event unitless
Bottle_NumBottle number unitless
time_localTime of sampling (local time zone) formatted as HH:MM unitless
time_GMTTime of sampling (GMT) formatted as HH:MM unitless
depthSample depth meters (m)
tempWater temperature degrees Celsius
salSalinity unitless
CTD_O2Oxygen measured by CTD micromolar (uM)
O2_sat_100pcnt100% oxygen saturation micromolar (uM)
O2_satPercent oxygen saturation unitless (percent)
fluor_chlaChlorophyll fluorescence. Reported in voltage (from the RV Sharp fluorometer sensor). volts
TATotal alkalinity mesaured by open cell Gran titration with semi-automatic AS-ALK2 Apollo Scitech titrator microles per kilogram (uM/kg)
DICDissolved inorganic carbon measured by infrared CO2 analyzer (AS-C3, Apollo Scitech) microles per kilogram (uM/kg)
pHpH (primary) measured by glass electrode, NBS buffers unitless (pH scale)
Particulate_MnOxParticulate Manganese oxide (MnOx). DL= 0.01 uM or 10 nM. micromolar (uM)
Particulate_MnOx_stdevStandard deviation of Particulate Manganese oxide micromolar (uM)
Dissolved_Mn2plusDissolved Mn2+ micromolar (uM)
Dissolved_Mn2plus_stdevStandard deviation of dissolved Mn2+ micromolar (uM)
Dissolved_Mn3plusDissolved Mn3+ where Mn3+ = [MnT - Mn2+] micromolar (uM)
Dissolved_Mn3plus_stdevStandard deviation of dissolved Mn3+ micromolar (uM)
Dissolved_MnTDissolved MnT micromolar (uM)
Dissolved_MnT_stdevStandard deviation of dissolved MnT micromolar (uM)
Dissolved_sulfideDissolved sulfide micromolar (uM)
Dissolved_filtered_Fe2plusDissolved filtered Fe2+. DL for Fe is 0.100 micromolar. micromolar (uM)
Dissolved_filtered_Fe2plus_stdevStandard deviation of dissolved filtered Fe2+ micromolar (uM)
Particulate_unfiltered_Fe2plusParticulate unfiltered Fe2+ micromolar (uM)
Particulate_unfiltered_Fe2plus_stdevStandard deviation of particulate unfiltered Fe2+ micromolar (uM)
Dissolved_filtered_Fe3plusDissolved filtered Fe3+ micromolar (uM)
Dissolved_filtered_Fe3plus_stdevStandard deviation of dissolved filtered Fe3+ micromolar (uM)
Particulate_unfiltered_Fe3plusParticulate unfiltered Fe3+ micromolar (uM)
Particulate_unfiltered_Fe3plus_stdevStandard deviation of particulate unfiltered Fe3+ micromolar (uM)
pH_secondarypH (secondary) measured by glass electrode, NBS buffers unitless (pH scale)
nanoparticulate_S0Nanoparticulate S(0) (micromolar (uM)
ISO_DateTime_UTCDate and time of sampling formatted to ISO8601 standard (yyyy-mm-ddTHH:MM); constructed using original date and time_GMT fields. yyyy-MM-dd'T'HH:mm:ss.SS


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Instruments

Dataset-specific Instrument Name
Generic Instrument Name
Niskin bottle
Generic Instrument Description
A Niskin bottle (a next generation water sampler based on the Nansen bottle) is a cylindrical, non-metallic water collection device with stoppers at both ends. The bottles can be attached individually on a hydrowire or deployed in 12, 24, or 36 bottle Rosette systems mounted on a frame and combined with a CTD. Niskin bottles are used to collect discrete water samples for a range of measurements including pigments, nutrients, plankton, etc.

Dataset-specific Instrument Name
Generic Instrument Name
CTD Sea-Bird
Dataset-specific Description
Samples were collected using R/V Sharp's Sea-Bird CTD.
Generic Instrument Description
Conductivity, Temperature, Depth (CTD) sensor package from SeaBird Electronics, no specific unit identified. This instrument designation is used when specific make and model are not known. See also other SeaBird instruments listed under CTD. More information from Sea-Bird Electronics.

Dataset-specific Instrument Name
Generic Instrument Name
CTD-fluorometer
Dataset-specific Description
R/V Sharp's CTD fluorometer
Generic Instrument Description
A CTD-fluorometer is an instrument package designed to measure hydrographic information (pressure, temperature and conductivity) and chlorophyll fluorescence.

Dataset-specific Instrument Name
AS-ALK2 Apollo Scitech titrator
Generic Instrument Name
Automatic titrator
Generic Instrument Description
Instruments that incrementally add quantified aliquots of a reagent to a sample until the end-point of a chemical reaction is reached.

Dataset-specific Instrument Name
Generic Instrument Name
Oxygen Sensor
Dataset-specific Description
O2 sensor equipped on R/V Sharp's CTD rosette
Generic Instrument Description
An electronic device that measures the proportion of oxygen (O2) in the gas or liquid being analyzed

Dataset-specific Instrument Name
AS-C3, Apollo Scitech infrared CO2 analyzer
Generic Instrument Name
CO2 Analyzer
Generic Instrument Description
Measures atmospheric carbon dioxide (CO2) concentration.


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Deployments

HRS1415

Website
Platform
R/V Hugh R. Sharp
Start Date
2014-08-18
End Date
2014-08-25


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Project Information

The role of soluble Mn(III) in the biogeochemical coupling of the Mn, Fe and sulfur cycles (Soluble ManganeseIII)

Coverage: Chesapeake Bay and coastal Atlantic Ocean


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.



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Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)

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