Ronald Benner Professor of Biological Sciences Primary Faculty in the Marine Science Program Ph.D., 1984, University of Georgia Office/Lab: 346 Sumwalt (803) 777-9561 Dr. Benner's email address is benner@biol.sc.edu Dr. Benner's C.V.

Microorganisms have a profound impact on the composition of the biosphere and global biogeochemical cycles.  Microbes play key roles in the cycling of bioactive elements, such as C, N and P, and in the transfer of these elements into complex food webs.  Bacterial growth and activity  are supported primarily by detrital material in both dissolved and particulate form.  Dissolved organic matter (DOM) is by far the most abundant form of reduced carbon and detrital material in the ocean, and it is one of the largest reactive reservoirs of organic carbon on Earth.  Dissolved and particulate organic matter (DOM and POM) are chemically complex, and they are derived from a variety of sources.  A primary research objective in my laboratory is to characterize the origins, compositions, transformations and fates of DOM and POM in freshwater, estuarine and marine environments.  In the ocean, combined carbohydrates and amino acids are the major reactive components of DOM, and ongoing studies are investigating rates of bacterial production and utilization of these compounds and the factors controlling bacterial growth and respiration.   Research on DOM and POM in large rivers (e.g. Amazon, Mississippi, Ob, Yenisei) indicates that it is derived primarily from decaying plant material in soils.  The DOM and POM in these rivers is rich in aromatic components, such as tannins and lignins, and is resistant to bacterial oxidation.  Photochemical reactions appear to play an important role in the decomposition of these biorefractory components.  Ongoing research projects in my laboratory are investigating various aspects of the cycling of organic matter in environments ranging from the Arctic Ocean to the Amazon River.

• Jenny Davis, Ph.D. student in Marine Science

• Nobuyuki Kawasaki, Ph.D. student in Marine Science

• Karl Kaiser, Ph.D. student in Marine Science

• Richard Daw, Ph.D. student in Marine Science
  
• Luc Tremblay , postdoctoral associate

Benner, R., P. Louchouarn, and R.M.W. Amon. 2005. Terrigenous dissolved organic matter in the Arctic Ocean and its transport to surface and deep waters of the North Atlantic. Global Biogeochem. Cycles. 19, GB2025, doi:10.1029/2004GB002398. (PDF)

Benner, R., B. Benitez-Nelson, K. Kaiser, and R. M. W. Amon. 2004. Export of young terrigenous dissolved organic carbon from rivers to the Arctic Ocean. Geophys. Res. Lett., 31, L05305, doi:10.1029/2003GL019251.(PDF)

Obernosterer, I., and R. Benner. 2004. Competition between biological and photochemical processes in the mineralization of dissolved organic carbon. Limnol. Oceanogr.. 49: 117-124.(PDF)

Benner, R., and K. Kaiser. 2003. Abundance of amino sugars and peptidoglycan in marine particulate and dissolved organic matter. Limnol. Oceanogr. 48: 118-128.(PDF)

Obernosterer, I., N. Kawasaki, and R. Benner. 2003. Phosphate limitation of respiration in the Sargasso Sea and uncoupling of P cycling in size fraction experiments. Aquat. Microb. Ecol. 32: 229-237.(PDF)

Benner, R. 2003. Molecular indicators of the bioavailability of dissolved organic matter, pp. 121-137, In: Aquatic Ecosystems: Interactivity of Dissolved Organic Matter, S.E.G.Findlay and R.L.Sinsabaugh (eds.), Academic Press.

Hernes, P. J., and R. Benner. 2003. Photochemical and microbial degradation of dissolved lignin phenols: Implications for the fate of terrigenous dissolved organic matter in marine environments. J. Geophys. Res., 108 (C9), doi: 10.1029/2002JC001421, 2003. (PDF)

Benner, R. 2002. Chemical composition and reactivity , pp. 59-90, In: Biogeochemistry of Marine Dissolved Organic Matter, D. Hansell and C. Carlson (eds), Academic Press.

Ogawa, H., Y. Amagai, I. Koike, K. Kaiser, and R. Benner. 2001. Production of refractory dissolved organic matter by bacteria. Science 292: 917-920. (PDF)

Amon, R. M. W., H.-P. Fitznar, and R. Benner. 2001. Linkages among the bioreactivity, chemical composition, and diagenetic state of marine dissolved organic matter. Limnol. Oceanogr. 46: 287-297. (PDF)

Ziegler, S., and R. Benner. 2000. Effects of solar radiation on dissolved organic matter cycling in a subtropical seagrass meadow. Limnol. Oceanogr. 45: 257–266. (PDF)

Ziegler, S., and R. Benner. 1999. Dissolved organic carbon cycling in a subtropical seagrass-dominated lagoon. Mar. Ecol. Prog. Ser., 180: 149-160.

Opsahl, S., R. Benner, and R. M. W. Amon. 1999. Major flux of terrigenous dissolved organic matter through the Arctic Ocean. Limnol. Oceanogr. 44: 2017-2023. (PDF)

Clark, L. L., E. D. Ingall, and R. Benner. 1998. Marine phosphorus is selectively remineralized. Nature 393: 426. (PDF)

McCarthy, M., J. I. Hedges, and R. Benner. 1998. Major bacterial contribution to marine dissolved organic nitrogen. Science 281: 231-234.(PDF)

Benner, R., and B. Biddanda. 1998. Photochemical transformations of surface and deep marine dissolved organic matter: Effects on bacterial growth. Limnol. Oceanogr. 43: 1373-1378. (PDF)

Opsahl, S., and R. Benner. 1997. Distribution and cycling of terrigenous dissolved organic matter in the ocean. Nature 386: 480-482. (PDF)

McCarthy, M., T. Pratum, J. I. Hedges, and R. Benner. 1997. Chemical composition of dissolved organic nitrogen in the ocean. Nature 390: 150-154. (PDF)

Skoog, A., and R. Benner. 1997. Aldoses in various size fractions of marine organic matter: implications for carbon cycling. Limnol. Oceanogr. 42: 1803-1813. (PDF)

Hedges, J. I., R. Keil, and R. Benner. 1997. What happens to terrestrial organic matter in the ocean? Org. Geochem. 27: 195-212. (PDF)

Amon, R. M. W., and R. Benner. 1996. Bacterial utilization of different size classes of dissolved organic matter. Limnol. Oceanogr. 41: 41-51. (PDF)

Benner, R., S. Opsahl, G. Chin-Leo, J. E. Richey, and B. Forsberg. 1995. Bacterial carbon metabolism in the Amazon River system. Limnol. Oceanogr. 40: 1262-1270. (PDF)

Opsahl, S., and R. Benner. 1995. Early diagenesis of vascular plant tissues: lignin and cutin decomposition and biogeochemical implications. Geochem. Cosmochim. Acta 59: 4889-4904. (PDF)

Pakulski, J. D., R. Benner, R. Amon, B. Eadie, and T. Whitledge. 1995. Community metabolism and nutrient cycling in the Mississippi River plume: Evidence for intense nitrification at intermediate salinities. Mar. Ecol. Prog. Ser. 117: 207-218.

Amon, R. M. W., and R. Benner. 1994. Rapid cycling of high-molecular-weight dissolved organic matter in the ocean. Nature 369: 549-552. (PDF)

Biddanda, B., S. Opsahl, and R. Benner. 1994. Plankton respiration and carbon flux through bacterioplankton on the Louisiana shelf. Limnol. Oceanogr. 39: 1259-1275. (PDF)

Benner, R., J.D. Pakulski, M. McCarthy, J.I. Hedges and P.G. Hatcher. 1992. Bulk chemical characterization of dissolved organic matter in the ocean. Science 255: 1561-1564. (PDF)

Benner, R., M. F. Fogel, E. K. Sprague, and R. E. Hodson. 1987. Depletion of 13C in lignin and its implications for stable carbon isotope studies. Nature 329: 708-710. (PDF)