Dr. Brian Roberts
Associate Professor; REU Program Director

Mailing Address:
Louisiana Universities Marine Consortium
DeFelice Marine Center
8124 Highway 56
Chauvin, Louisiana 70344

Phone: 985-851-2821

Educational Background

  • Ph.D., 2004, Ecology and Evolutionary Biology
    Cornell University, Ithaca, NY
  • M.A., 1996, Marine Biology
    Boston University Marine Program, Marine Biological Laboratory, Woods Hole, MA
  • B.S., 1995, Biology and Philosophy
    College of William and Mary, Williamsburg, VA

Research Interests

  • The Roberts Lab is interested in understanding how ecosystems transform and retain nutrients and energy. We are particularly interested in examining how the mechanisms regulating the autotrophic/heterotrophic balance and the biogeochemical cycling and transport of materials along the continuum from headwater streams and lakes to large rivers, wetlands, estuaries, and open-ocean ecosystems are altered as a result of human perturbations to the landscape (e.g. land use changes, fertilizer applications, climate change, oil spills, etc.). We are also interested in examining how restoration efforts might mitigate some of these deleterious impacts.

Current Projects

  • Current research in the Roberts Lab is broadly focused in three areas: 1) ecosystem ecology and biogeochemistry; 2) human-induced environmental impacts on aquatic ecosystems; and 3) restoration ecology. Our research team is currently involved in projects in multiple ecosystem types including headwater streams, rivers, river deltas, baldcypress swamps, salt marshes, estuaries and coastal oceans. The interdisciplinary and collaborative nature of our research lends itself to providing numerous research opportunities to students.
  • Biogeochemical cycling in estuaries and continental shelf ecosystems
  • Coastal Hypoxia in the northern Gulf of Mexico
  • Primary and secondary production on nGOM oil and gas structures
  • Influence of changes in salinity regimes and vegetation on wetland biogeochemistry
  • Effects of the Macondo Oil Spill on Coastal Ecosystems
    • Wetland biogeochemistry, plant ecology and microbial ecology
    • Food webs and carbon flow in marsh ecosystems
  • Stream Ecosystem Metabolism and Biogeochemistry


Research Group

  • Natalie Ceresnak, MS Student (LSU)
    • B.S., 2015, Environmental Science
      University of Scranton, Scranton, PA

  • Ariella Chelsky, Postdoctoral Research Associate
    • B.S., 2009, Marine Biology
      University of British Columbia, Vancouver, BC, Canada

    • PhD, 2015, Marine Ecology and Biogeochemistry
      Griffiths University, Gold Coast, Australia

  • Becky Forgrave, Research Assistant
    • B.A., 2014, Environmental Science (Specialization: Chemistry)
      Colby College,, Waterville, ME

  • Samantha Setta, Research Assistant
    • B.A., 2014, Biology (Specialization: Marine and Freshwater Biology)
      University of Texas, Austin, TX

  • Hillary Sullivan, Research Assistant
    • B.A., 2013, Environmental Science Conservation Biology
      Clark University, Worcester, MA

    • M.S., 2014, Biology
      Clark University, Worcester, MA

  • Regina Bledsoe, Student worker
    • B.S., 2015, Environmental Science
      Nicholls State University, Thibodaux, LA


  • PDFs are available for all of the published articles listed below. The PDF links at the end of each article will take you directly to the article on the journal's website. If the article is a free-acess publication or if you or your library has an on-line subscription to the journal, you will be able to download and/or print the article directly from the link. If you do not have access to the pdf and would like a reprint of the article, please send me an email.
  • Roberts BJ, Doty SM. 2015. Spatial and temporal patterns of benthic respiration and net nutrient fluxes in the Atchafalaya River Delta Estuary. Estuaries and Coasts. DOI: 10.1007/s12237-015-9965-z. [pdf]
  • Middleton BA, Johnson D, Roberts BJ. 2015. Hydrologic remediation for the Deepwater Horizon Incident drove ancillary primary production increase in coastal swamps. Ecohydrology. DOI: 10.1002/eco.1625.[pdf]
  • Marton JM, Roberts BJ, Bernhard AE, Giblin AE. 2015. Spatial and temporal variability of nitrification potential and ammonia-oxidizer abundances in Louisiana salt marshes. Estuaries and Coasts. DOI: 10.1007/s12237-015-9943-5. [pdf]
  • Able KW, Lopez-Duarte PC, Fodrie FJ, Jensen OP, Martin CW, Roberts BJ, Valenti J, O'Connor K, Halbert SC. 2014. Fish Assemblages in Louisiana Salt Marshes: Effects of the Macondo Oil Spill. Estuaries and Coasts. DOI: 10.1007/s12237-014-9890-6. [pdf]
  • Joye SB, Montoya JP, Murawski SA, Özgökmen TM, Wade TL, Montuoro R, Roberts BJ, Hollander DJ, Jeffrey WH, Chanton JP. 2014. A Rapid Response Study of the Hercules Gas Well Blowout. Eos 95(38): 341-342. DOI: 10.1002/2014EO380002 [pdf]
  • Hitchcock G, Lenes J, Benner R, Daly K, Murrell M, Roberts B, Walsh J. 2014. Chapter 7: Respiration. In: Benway HW, Coble PG (Editors). Report of the U.S. Gulf of Mexico Carbon Cycle Synthesis Workshop, March 27-28, 2013, Ocean Carbon and Biogeochemistry Program and North American Carbon Program, pp. 39-43. [pdf]
  • Hooper-Bui, LM, Rabalais NN, Engel AS, Turner RE, McClenachan G, Roberts B, Overton EB, Justic D, Strudivant K, Brown K, Conover J. 2014. Overview of Research into the Coastal Effects of the Macondo Blowout from the Coastal Waters Consortium: A GoMRI Consortium. International Oil Spill Conference Proceedings May 2014, Vol. 2014, No. 1 (May 2014) pp. 604-617. DOI: http://dx.doi.org/10.7901/2169-3358-2014.1.604.[pdf]
  • Marton JM and Roberts BJ. 2014. Spatial variability in phosphorus sorption dynamics in Louisiana salt marshes.JGR-Biogeosciences. doi: 10.1002/2013JG002486.[pdf]
  • Rosenheim B.E., Roe K.E., Roberts B.J., Kolker A.S, Allison M.A., Johannesson K.H. 2013. River discharge influences on particulate organic carbon age structure in the Mississippi/Atchafalaya River System. Global Biogeochemical Cycles 27:1-13. doi: 10.1029/2012GB004339.[pdf]
  • Lutz BD, Bernhardt ES, Roberts BJ, Mulholland PJ, Cory RM. 2012 Distinguishing terrestrial and autochthonous organic matter dynamics in a forested stream using kinetic enrichments and fluorescence spectroscopy. Limnology and Oceanography 57(1): 76-89.[pdf]
  • Lutz BD, Bernhardt ES, Roberts BJ, Mulholland PJ. 2011. Examining the coupling of carbon and nitrogen cycles in Appalachian streams: the role of dissolved organic nitrogen. Ecology 92(3): 720-732.[pdf]
  • Hill WR, Roberts BJ, Francoeur SN, Fanta SE. 2011. Resource energy and the autotrophic: heterotrophic balance in experimental streams. Journal of Ecology 99:454-463. DOI: 10.1111/j.1365-2745.2010.01785.x[pdf]
  • Fanta SE, Hill WR, Smith TB, Roberts BJ. 2010. Applying the light : nutrient hypothesis to stream periphyton. Freshwater Biology doi:10.1111/j.1365-2427.2009.02309.x[pdf]
  • Hill WR, Fanta SE, Roberts BJ. 2009. Combined effects of phosphorus and light on stream algae: implications for establishing stream nutrient criteria. Limnology and Oceanography 54(1):368-380.[pdf]
  • Mulholland PJ, Roberts BJ, Hill WR, Smith JG. 2009. Stream ecosystem responses to the 2007 spring freeze in the Southeastern United States: unexpected effects of climate change. Global Change Biology 15(7): 1767-1776. doi: 10.1111/j.1365-2486.2009.01864.x[pdf]
  • Hill WR, Fanta SE, Roberts BJ. 2008. 13C dynamics in benthic algae: effects of light, phosphorus, and biomass development. Limnology and Oceanography 53(4): 1217-1226. [pdf]
  • Roberts BJ, Mulholland PJ. 2007. In-stream biotic control on nutrient biogeochemistry in a forested headwater stream, West Fork of Walker Branch. JGR-Biogeosciences 112, G04002, doi:10.1029/2007JG000422 [pdf]
  • Roberts BJ, Mulholland PJ, Hill WR. 2007. Multiple scales of temporal variability in ecosystem metabolism rates: results from two years of continuous monitoring in a forested headwater stream. Ecosystems 10(4): 588-606. doi: 10.1007/s10021-007-9059-2[pdf]
  • Roberts BJ, Mulholland PJ, Houser JN. 2007. Effects of upland disturbance and in-stream restorations on hydrodynamics and ammonium uptake in headwater streams. Journal of the North American Benthological Society 26(1):38-53. [pdf]
  • Roberts BJ, Howarth RW. 2006. Nutrient and light availability regulate the relative contribution of autotrophs and heterotrophs to respiration in freshwater pelagic ecosystems. Limnology and Oceanography 51(1): 288-298. [pdf]
  • Roberts BJ, Russ ME, Ostrom NE. 2000. Rapid and precise determination of δ18O of dissolved and gaseous di-oxygen via gas chromatography-isotope ratio mass spectrometry. Environmental Science and Technology 34(11):2337-2341.[pdf]
  • Heberlig L, Valiela I, Roberts BJ. 1997. A field verification of the Waquoit Bay Nitrogen Loading Model. Biological Bulletin 193: 294-295.[pdf]
  • Lee RY, Joye SB, Roberts BJ, Valiela I. 1997. Release of N2 and N2O from salt marsh sediments subject to different land-derived nitrogen loads. Biological Bulletin 193:292-293.[pdf]