Deborah A. Bronk

• Professor
• B.S., University of Miami,
  Coral Gables, FL
• Ph.D., University of Maryland,
  Horn Point Laboratory

• Research Interests
• Current Projects
• Recent Field Work
• Current Students
• Past Students
• Courses Taught or Teaching
• Faculty/Student Awards
• Professional Memberships
• Publications

Bronk Lab Webpage

Research Interests

I am interested in the fluxes of nitrogen in open ocean, coastal, and estuarine environments with emphasis on the role of dissolved organic nitrogen (DON) in microbial food webs. My early work involved extensive method development with the goal of quantifying in situ rates of DON release and uptake using 15N tracer techniques. I now use these techniques to address a host of questions relating to the release of DON from phytoplankton and zooplankton and subsequent reincorporation of DON as a nitrogen source for phytoplankton and bacteria. More recently I have investigated photochemical processes as a mechanism that facilitates the uptake of organic nitrogen by both phytoplankton and bacteria. I continue to be intrigued by methods development, and I have most recently been working on linking flow cytometry with 15N tracer techniques to quantify nitrogen flow into autotrophs versus heterotrophs in open ocean systems.

Current Projects

• Quantification and modeling of DOC and DON release in marine systems: a study of increasing trophic complexity
  Funded by NSF-Biocomplexity. 9/02 to 8/07. $1,699,000.
  Deborah A. Bronk (PI, VIMS), Walker O. Smith (Co-PI, VIMS), Deborah Steinberg (Co-PI, VIMS), David Malmquist (Co-PI, VIMS), Eric Wommack (Co-PI, University of Delaware), Craig Carlson (Co-PI, University of California at Santa Barbara), Raleigh Hood (Co-PI, University of Maryland, Horn Point Laboratory), and Dan Repeta (Co-PI, Woods Hole Oceanographic Institution)
• Karenia nutrient dynamics in the Eastern Gulf of Mexico
  Funded by EPA ECOHAB.
  September 2006 to August 2011 Bronk, Co-PI. Bronk part $499,823. Lead PI Cindy Heil (FFWCC)
• Nitrogen Preferences and Uptake Kinetics in Cultures and Field Populations of the Florida Red Tide Dinoflagellate Karenia brevis
  Funded by Florida Fish and Wildlife Conservation Commission.
  October 2005 to April 2006 Bronk, PI. $25,000.
• The Ecology and Genomics of CO2 Fixation in Oceanic River Plumes.
  Funded by DOE.
  February 2005 to January 2008. Bronk, Co-PI Bronk part $117,039. Lead PI John Paul (USF)
• Molecular approaches for in situ study of nitrate utilization by marine bacteria.
  Funded by DOE.
  December 2003 to November 2006. Bronk, Co-PI. Bronk part $186,160. Lead PI Marc Frischer (SkIO)

Past Research Projects

• Geochemical Rate/RNA Integration Study (GRIST): A Pilot Field Experiment for Inter-Calibration of Biogeochemical Flux and Nucleic Acid Measurements
  Funded by DOE. 6/02 to 5/03. ~$400,000.
  Lee Kerkhoff (PI, Rutgers), Deborah A. Bronk (PI, VIMS), and others.
• Fate of recently fixed nitrogen in the eastern Gulf of Mexico: Does the regeneration of nitrogen fixed by Trichodesmium support the growth development of G. breve blooms?
  Funded by NSF-Biological Oceanography. 5/01 to 4/04. ~$700,000.
  Cindy Heil (PI, University of South Florida), Deborah A. Bronk (Co-PI, VIMS), and Margie Mulholland (Co-PI, Old Dominion University)
• Molecular approaches for in situ study of nitrate utilization by marine bacteria.
  Funded by DOE. 12/00 to 11/03.
  Mark Frischer (PI, SkIO), Peter Verity (Co-PI, SkIO), Melissa Booth (Co-PI,SkIO), Deborah Bronk (Co-PI, VIMS) and Matt Gilligan (Co-PI, SSU).
• Coastal eutrophication in the southeastern U.S.: Nitrogen versus phosphorus limitation and the role of organic nitrogen
  Funded by Georgia Sea Grant. Completed 3/02.
  Deborah A. Bronk (PI, UGA/VIMS)
• Coastal eutrophication: Organic versus inorganic nitrogen as a source of coastal productivity
  Funded by Georgia Sea Grant.
  Deborah A. Bronk (PI, UGA)
• Molecular approaches for in situ identification of nitrate utilization by marine bacteria and phytoplankton
  Funded by DOE.
  Mark Frischer (PI, SkIO), Peter Verity (Co-PI, SkIO), Melissa Booth (Co-PI,SkIO), Deborah Bronk (Co-PI, VIMS) and Matt Gilligan (Co-PI, SSU).
• New and regenerated production in the Southern Ocean: Ross Sea studies (U.S. JGOFS)
  Funded by NSF - Office of Polar Programs
  Bill Cochlan (PI, SFSU) and Deborah A. Bronk (Co-PI, UGA)
• Inputs and fates of organic nitrogen in two land-margin ecosystems: Chesapeake Bay and Georgia coastal rivers
  Funded by NSF, Biological Oceanography and Environmental Geochemistry and Biogeochemistry.
  Patricia M. Glibert (PI, UMd) and Deborah A. Bronk (Co-P.I, UGA).

Recent Field Work

Recent project pics

• 2006 (November) – R/V Pelican (LUMCON), scientist, 10-day cruise from Trinidad to Puerto Rico to measure nitrogen flux rates as part of a DOE-funded project.
• 2006 (April) – R/V Point Sur (Moss Landing Marine Laboratory), Chief scientist, 9-day cruise in the Santa Barbara channel to measure carbon and nitrogen flux rates as part of the Biocomplexity project.
• 2005 (April) – Four week mesososm study in Bergen, Norway.
• 2005 (April) – R/V Cape Henlopen (University of Delaware), Chief scientist, 7-day cruise in Chesapeake Bay to measure carbon and nitrogen flux rates as part of the Biocomplexity project.
• 2004 (August) – R/V Cape Henlopen (University of Delaware), scientist, 5-day cruise in Chesapeake Bay to measure nitrogen flux rates.
• 2004 (July) – R/V Cape Henlopen (University of Delaware), Chief scientist, 7-day cruise in Chesapeake Bay to measure carbon and nitrogen flux rates as part of the Biocomplexity project.
• 2003 (March) – Four week mesososm study in Bergen, Norway.
• 2003 (June) – R/V Pelican (LUMCON), 14-day cruise in the Gulf of Mexico to quantify nitrogen fixation and organic nitrogen release rates by Trichodesmium.

Current Students

Lab Group

• Marta Sanders, Lab Manager
• Quinn Roberts, Senior Research Technician
• Paul Bradley, Ph.D. student
• Lynn Killberg, Ph.D. student
• Steve Baer, Ph.D. student

Past Students

• Joel Hoffman, Ph.D. completed May 2006.
• Jason See, Ph.D. completed December 2004.
• Dirk Koopmans, Masters student at University of Georgia. M.S. completed December 2000.

Courses Taught or Teaching

• Spring 2007 - MSCI 502: Coordinator and contributor to Coastal and Estuarine Processes and Issues, SMS/VIMS, 48%
• Fall 2006 - MSCI 655: Stable Isotope Biogeochemistry, SMS/VIMS, 50%.
• Fall 2006 - MSCI 501L: Fundamentals of Marine Sciences Lab, SMS/VIMS, 7%
• Spring 2006 - MSCI 502: Coordinator and contributor to Coastal and Estuarine Processes and Issues, SMS/VIMS, 48%.
• Spring 2005 - MSCI 502: Coordinator and contributor to Coastal and Estuarine Processes and Issues, SMS/VIMS, 20%
• Fall 2005 - MSCI 501L: Fundamentals of Marine Sciences Lab, SMS/VIMS, 7%
• Spring 2004 - MSCI 502: Coordinator and contributor to Coastal and Estuarine Processes and Issues, SMS/VIMS, 20%
• Fall 2004 - MS 501L: Fundamentals of Marine Sciences Lab, SMS/VIMS, 7%
• Fall 2004 - MS 698: Isotope Biogeochemistry, SMS/VIMS, 50%, 50%

Faculty/Student Awards

• 2005. Krispy Kreme Award recipient. Award was given in recognition of effective use of a doughnut metaphor as applied to DON availability at the Significant Processes, Observations, and Transformation in Oceanic Nitrogen (SPOT ON) workshop, Warnemunde Germany.
• 1996. Lindeman Award recipient. Award is given annually by the American Society of Limnology and Oceanography for the outstanding paper in aquatic sciences by a young scientist.
• 1995. Recipient of the Antarctic Service Medal.
• 1993. Selected for participation at the Dissertations Symposium on Chemical Oceanography (DISCO) meeting in March 1993, Honolulu, Hawaii.

Professional Membership Committees

• 2007-present   Chair, Ocean Time-Series Advisory Committee (OTSAC, NSF and OCB).
• 2007-present   Chair, ASLO's Meeting Committee.
• 2006-present   Member of ASLO's Education Committee's Sub-committee on web-based lectures.
• 2006-present   Scientific advisor to the Chesapeake Bay's Scientific and Technical Advisory Committee on DON bioavailability in wastewater.
• 2005-2007   Co-chair of 2007 ASLO meeting in Santa Fe, NM.
• 2006   Co-organizer and co-chair of a special session, In search for allochthony, with my former student, Joel Hoffman, at the 2007 ASLO meeting in Santa Fe, NM.
• 2006-present   Invited member of the eight member Ocean Carbon and Biogeochemistry (OCB) Scientific Steering Committee (SSC) assembled by the National Science Foundation. The role of OCB SSC is to define goals and develop programs for research into ocean biogeochemistry.
• 2006   Invited participant in the State of the Research on Red Tide in the Gulf of Mexico workshop at Mote Marine Laboratory in Sarasota, FL.
• 2006   Invited participant in Ocean Carbon and Climate Change workshop in Woods Hole, MA.
• 2005   Invited participant and invited speaker at the Significant Processes, Observations, and Transformations in Ocean Nitrogen (SPOT-ON) in Warnemunde, Germany.
• 2003-2007   Member of ASLO's Publications Committee.
• 2003-2006   Elected to ASLO's Board of Directors as a Member-at-Large.
• Reviewer for: Acta Oecologica, Aquatic Microbial Ecology, Biogeochemistry, Critical Reviews in Environmental Science and Technology, Deep Sea Research I, Deep Sea Research II, Ecology, Environmental Science and Technology, Estuaries, Estuaries and Coasts, Estuarine Coastal and Shelf Science, Geochim Costochim Acta, Geophysical Research Letters, Hydrobiologia, Journal of Air and Waste Management Association, Journal of Experimental Marine Biology and Ecology Journal of Geophysical Research Ocean, Journal of Marine Research, Journal of Phycology, Journal of Plankton Research, Limnology and Oceanography, Limnology and Oceanography Methods, Marine Biology, Marine Chemistry, Marine Ecology Progress Series, Microbial Ecology, New Phytologist, Ophelia, Science, Water resources.
• Reviewer for: Environmental Protection Agency, National Environmental Research Council, National Underwater Research Council (NURC/UNCW), National Science Foundation (Biological Oceanography, Chemical Oceanography, Environmental Geochemistry and Biogeochemistry, Biocomplexity, Research Coordination Networks), National Oceanographic and Atmospheric Administration (ECOHAB, GOMEX, Sea Grant), US-Israel Binational Research Foundation, Water Resources Research Council.
• Panelist for: NSF Chemical Oceanography, NSF Biocomplexity in the Environment – Coupled Biogeochemical Cycles (BE-CBC), NOAA Ecology of Harmful Blooms (ECOHAB), NSF Environmental Geochemistry and Biogeochemistry, NSF Research Coordination Networks (RCN).

Publications

DON Release

• Bronk, D. A. and D. Steinberg.  In press.  Nitrogen regeneration.  In: Nitrogen in the Marine Environment. Capone, D. G., Bronk, D. A., Mulholland, M. and Carpenter, E. (eds).  Elsevier Press.
  
• Bronk, D. A. and B. B. Ward.  2005.  Inorganic and organic nitrogen cycling in the Southern California Bight. Deep Sea Research I.  52:  2285-2300.
  
• Bronk, D. A.  2002.  Dynamics of dissolved organic nitrogen.  In Biogeochemistry of Marine Dissolved Organic Matter.  Eds.  Hansell, D. A. and Carlson, C. A.  pg. 153-247.
  
• Ward, B. B. and D. A. Bronk.  2001.  Net nitrogen uptake and DON release in surface waters: importance of trophic interactions implied from size fractionation experiments.  Marine Ecology Progress Series. 219: 11-24.
  
• Bronk, D. A. and B. B. Ward.  2000.  Magnitude of DON release relative to gross nitrogen uptake in marine systems. Limnology and Oceanography. 45: 1879-1883.
  
• Bronk, D. A. and B. B. Ward.  1999.  Gross and net nitrogen uptake and DON release in the euphotic zone of Monterey Bay, California. Limnology and Oceanography.  44: 573-585.
  
• Bronk, D. A.  1999.  Rates of NH4+ uptake, intracellular transformation and dissolved organic nitrogen release in two clones of marine Synechococcus spp. Journal Plankton Research. 21: 1337-1353.
  
• Bronk, D. A. and P. M. Glibert.  1994.  The fate of the missing 15N differs among marine systems. Limnology and Oceanography. 39: 189-194.
  
• Bronk, D. A., P. M. Glibert and B. B. Ward.  1994.  Nitrogen uptake, dissolved organic nitrogen release and new production. Science. 265: 1843-1846.
  
• Bronk, D. A. and P. M. Glibert.  1993.  Application of a 15N tracer method to the study of dissolved organic nitrogen uptake during spring and summer in Chesapeake Bay. Marine Biology. 115: 501-508.
  
• Bronk, D. A. and P. M. Glibert.  1993.  Contrasting patterns of dissolved organic nitrogen release by two size fractions of estuarine plankton during a period of rapid NH4+ consumption and NO2- production. Marine Ecology Progress Series. 96: 291-299.
  
• Bronk, D. A. and P. M. Glibert.  1991.  A 15N tracer method for the measurement of dissolved organic nitrogen release by phytoplankton. Marine Ecology Progress Series. 77: 171-182.

DIN and DON uptake

• #Bronk, D. A. and L. Campbell.  In preparation.  Autotrophic versus heterotrophic uptake of inorganic and organic nitrogen: linking flow cytometry with mass spectrometry. 
• #*Bradley, P. and D. A. Bronk.  In preparation.  Cross system comparison of autotrophic-specific nitrogen uptake in the ocean: implications for new and regenerated production.
• *Bradley, P. B. and D. A. Bronk.  Submitted.  Autotrophic versus heterotrophic nitrogen uptake in Chesapeake Bay determined using flow cytometry and 15N tracer techniques. 
• *Sanderson, M. P., D. A. Bronk, J. C. Nejstagaard, A. F. Sazhin, P. G.Verity and M. E. Frischer. In revision.  Inorganic and organic nitrogen uptake during a Phaeocystis bloom in a Norwegian Fjord: A mesocosm study.
• Nejstgaard, J. C., M. E. Fischer, P. G. Verity, J. T. Anderson, A. Jacobsen, M. J. Zirbel, A. Lersen, J. Martinez, A. F. Sazhin, T. Walters, S. J. Whipple, S. Borett, B. C. Patten, J. D. Long, D. A. Bronk.  2006.  Temporal patters in planktonic food web development in mesocosms with added nutrients and Phaeocystis.  Aquatic Microbial Ecology.
• Bronk, D. A. and K. J. Flynn.  2006.  Algal cultures as a tool to study the cycling of dissolved organic nitrogen.  In: Algal Cultures, Analogues of Blooms and Applications. Ed. S. R. V Durvasula. pp. 301-341.
• Wawrick, B. J., H. Paul, D. A. Bronk, D. John and M. Gray.  2004.  Preferential uptake of ammonium in the presence of elevated nitrate concentrations by phytoplankton in the offshore Mississippi plume. Aquatic Microbial Ecology. 35: 175-184.
• Cochlan, W. P. and D. A. Bronk.  2003.  Effects of ammonium on nitrate utilization in the Ross Sea, Antarctica: Implications for f-ratio estimates.  In: Biogeochemistry of the Ross Sea.  DiTullio, G. R. and Dunbar, R. B. (eds). Antarctic Research Series.  78: 159-178.
• Allen, A.E., M. H. Howard-Jones, M. G. Booth, M. E. Frischer, P. G. Verity, D. A. Bronk and M. P. Sanderson.  2002.  Importance of heterotrophic bacterial assimilation of ammonium and nitrate in the Barents Sea during summer. Journal Marine Science. 38: 93-108.
• Cochlan, W. P., D. A.Bronk and K. H. Coale.  2002.  Trace metals and nitrogenous nutrition of Antarctic phytoplankton: experimental observations in the Ross Sea.  Deep-Sea Research. 49: 3365-3390.
• Cochlan, W. P. and D. A. Bronk.  2001.  Nitrogen uptake kinetics in the Ross Sea, Antarctica.  Deep-Sea Research II. 48: 4127-4153.

DON bioavailability

• Bronk, D. A., J. H. See, P. Bradley, and L. Killberg.  2007.  DON as a source of bioavailable nitrogen for phytoplankton.  Biogeosciences. 4: 283-296.
• *See, J. H, D. A. Bronk, and A. Lewitus.  2006. Uptake of Spartina-derived humic nitrogen by estuarine phytoplankton. Limnology and Oceanography.
• Wiegner, T. N., S. P. Seitzinger, P. Glibert, and D. A. Bronk.  2006.  Influence of watershed land use on riverine dissolved organic matter composition and bioavailablility.  Aquatic Microbial Ecology.  43:  277-287.
• Berman, T. and D. A. Bronk.  2003.  Dissolved Organic Nitrogen: a dynamic participant in aquatic ecosystems.  Aquatic Microbial Ecology.  31: 273-305.
• Bronk, D. A.  2002.  Dynamics of dissolved organic nitrogen.  In Biogeochemistry of Marine Dissolved Organic Matter.  Eds.  Hansell, D. A. and Carlson, C. A.  pg. 153-247.
• Lomas, M. W., T. M. Trice, P. M. Glibert, D. A. Bronk, J. J. McCarthy.  2002.  Temporal and spatial dynamics of urea concentrations in Chesapeake Bay:  Biological versus physical forcing.  Estuaries.  25: 469-482.

Linking carbon and nitrogen cycling

• Hoch, M. P. and D. A. Bronk.  In press.  Relative availability of nitrogen, phosphorus, and carbon to bacterioplankton in the Eastern Tropical North Pacific assessed by an enzymatic approach.  J. Env. Mar. Biol. Ecol.
• Nejstgaard, J. C., M. E. Fischer, P. G. Verity, J. T. Anderson, A. Jacobsen, M. J. Zirbel, A. Lersen, J. Martinez, A. F. Sazhin, T. Walters, S. J. Whipple, S. Borett, B. C. Patten, J. D. Long, D. A. Bronk.  2006.  Temporal patters in planktonic food web development in mesocosms with added nutrients and Phaeocystis.  Aquatic Microbial Ecology.
• Bronk, D. A., P. M. Glibert, T. C. Malone, E. Sahlstenand and S. Banahan.  1998.  Inorganic and organic nitrogen cycling in Chesapeake Bay: autotrophic versus heterotrophic processes and relationships to carbon flux.  Aquatic Microbial Ecology. 15: 177-189.
• John, D. E., Z.A. Wang, X. Liu, R.H. Byrne, J.E. Corredor, J.M. López, A. Cabrera, D.A. Bronk, R. F. Tabita, and J.H. Paul.  In press.  Carbon fixation gene (RuBisCO) transcripts and CO2 flux in the Mississippi River plume. International Society of Microbial Ecology Journal.

N2 fixation

• #Bronk, D. A., M. P. Sanderson, M. R. Mulholland, C. A. Heil and J. M. O'Neil.  In preparation.  Dissolved inorganic and organic nitrogen uptake by Trichodesmium in the Gulf of Mexico.
• Mulholland, M.R., P. W. Bernhardt, C. A. Heil, D. A. Bronk and J. M. O’Neil.  2006.  Nitrogen fixation and release of fixed nitrogen in the Gulf of Mexico. Limnology and Oceanography.  51 (4): 1762-1776.
• Mulholland, M., D. A. Bronk and D. G. Capone.  2004.  Dinitrogen fixation and release of ammonium and dissolved organic nitrogen by Trichodesmium IMS101.  Aquatic Microbial Ecology. 37: 85-94.
• Glibert, P.M. and D. A. Bronk.  1994.  Release of dissolved organic nitrogen by marine diazotrophic cyanobacteria, Trichodesmium spp.  Applied Environmental Microbiology. 60: 3996-4000.

Harmful Algal Blooms

• # Bronk, D. A., Killberg, L., M. Sanderson, M. Mulholland, and C. Heil.  In preparation.  Nitrogen uptake kinetics in field populations of Karenia brevis.
• Bronk, D. A., M. P. Sanderson, M. R. Mulholland, C. A. Heil and J. M. O'Neil.  2004.  Organic and inorganic nitrogen uptake kinetics in field populations dominated by Karenia brevis.  In: Steidinger, K. A., J. H. Landsberg, C. R. Tomas and G. A. Vargo (Eds.), Harmful Algae 2002.  Florida Fish and Wildlife Conservation Commission, Florida Institute of Oceanography and Intergovernmental Oceanographic Commission of UNESCO, St. Petersberg, Florida, USA. pp. 80-82. (peer-reviewed book)
• Heil, C. A., M. R. Mulholland, D. A. Bronk, P. Bernhardt and J. M. O'Neil.  2004.  Bacterial and size fractionated primary production within a large Karenia brevis bloom on the west Florida shelf.  In: Steidinger, K. A., J. H. Landsberg, C. R. Tomas and G. A. Vargo (Eds.), Harmful Algae 2002.  Florida Fish and Wildlife Conservation Commission, Florida Institute of Oceanography and Intergovernmental Oceanographic Commission of UNESCO, St. Petersberg, Florida, USA. pp. 38-40. (peer-reviewed book)
• Mulholland, M. R., C. A. Heil, D. A. Bronk, J. M. O'Neil and P. Bernhardt.  2004.  Does nitrogen regeneration from the N2 fixing cyanobacteria Trichodesmium spp. fuel Karenia brevis blooms in the Gulf of Mexico?  In: Steidinger, K. A., J. H. Landsberg, C. R. Tomas and G. A. Vargo (Eds.), Harmful Algae 2002.  Florida Fish and Wildlife Conservation Commission, Florida Institute of Oceanography and Intergovernmental Oceanographic Commission of UNESCO, St. Petersberg, Florida, USA. pp. 47-49. (peer-reviewed book)

Chemical characterizations and analyses

• Bronk, D. A., Q. Roberts, K. C. Filippino, and C. Carlson.  In preparation.  Measurement of dissolved organic nitrogen concentrations after removal of NH4+ and NO3-/NO2-. 
• *See, J. H. and D. A. Bronk.  2005.  Changes in molecular weight distributions, C:N ratios and chemical structures of estuarine humic substances with respect to season and age.  Marine Chemistry.  97:  334-346.
• Sharp, J. H. and others including D. A.  Bronk.  2002.  A preliminary methods comparison for measurement of dissolved organic nitrogen in seawater.  Marine Chemistry.  78: 171-184.
• Bronk, D. A., M. W. Lomas, P. M. Glibert, K. J. Schukert and M. P. Sanderson.  2000.  Total dissolved nitrogen analysis:  comparison between the persulfate, UV and high temperature oxidation methods.  Marine Chemistry.  69: 163-178.
• McCarthy, M. D. and D. A. Bronk.  In Press.  Analytical methods for nitrogen chemical characterization and flux rates.  In: Nitrogen in the Marine Environment. Capone, D. G., Bronk, D. A., Mulholland, M. and Carpenter, E. (eds).  Elsevier

Photochemistry

• *See, J. H. and D. A. Bronk.  In preparation.  An examination of salinity-reactive humic nitrogen exposed to simulated sunlight: Are we underestimating the photochemical release of NH4+ from dissolved organic nitrogen? 
• #Bronk, D. A., M. P. Sanderson, and D. Koopmans.  In preparation. Contribution #of photochemical production of labile nitrogen to plankton nutrition in an open ocean, continental shelf, and two riverine ecosystems. 
• *Koopmans, D. J. and D. A. Bronk.  2002.  Photochemical production of inorganic nitrogen from dissolved organic nitrogen in waters of two estuaries and adjacent surficial groundwaters.  Aquatic Microbial Ecology.  26: 295-304.
• Bushaw, K. L., R. G. Zepp, M. A. Tarr, D. Schulz-Jander, R. A. Bourbonniere, R. E. Hodson, W. L. Miller, D. A. Bronk and M. A. Moran.  1996.  Photochemical release of biologically labile nitrogen from dissolved organic matter. Nature.   381: 404-407.

Groundwater

• Joye, S.B., D.A. Bronk, D. J. Koopmans, and W. S. Moore. 2006. Evaluating the potential importance of groundwater-derived carbon, nitrogen, and phosphorus inputs to South Carolina and Georgia coastal ecosystems. In: G.S. Keleppel, M.R. De Voe and M.V. Rawson (Editors), Changing Land Use Patterns in the Coastal Zone. Springer, New York, pp. 139-178.

Natural abundance food web studies

• *Hoffman, J. C., D. A. Bronk, and J.E. Onley.  In press.  Heterogeneous use of nursery habitat identified in young American shad using stable isotopes.  Transactions of the American Fisheries Society.
• *Hoffman, J. C., K.E. Limburg, D. A. Bronk, and J.E. Onley.  2007.  Overwintering habitats of migratory juvenile American shad in Chesapeake Bay.  Environmental Biology of Fishes. 
• *Hoffman, J. C. and D. A. Bronk.  2006.  Inter-annual variability in stable carbon and nitrogen isotope biogeochemistry of the Mattaponi River, Virginia. Limnology and Oceanography.