People | Anthony Aufdenkampe

• B.A., Chemistry, Dartmouth College, 1991.
• M.S., Chemical Oceanography, University of Washington, 1998.

• Investigate processes of organic matter cycling throughout watersheds — from soils to rivers to estuaries.
• Elucidate the interplay between degradation and sorption processes in determining the composition and ultimate fate of organic matter within river systems.
• Employ diverse analytical and experimental techniques to answer hypothesis-driven questions.
  • Inorganic: Concentrations, isotopic compositions and fluxes of CO2, O2, nutrients and major ions.
  • Organic: Stable and radio- isotopes (13C, 14C, 15N, etc.), elemental and biochemical compositions (amino acids, lignins, etc.) and spectroscopy (NMR, IR, etc.).
  • Biological: Incubations to assess rates of total heterotrophic respiration, and microbial uptake and transformation of specific compounds (NO3, NH4, organic substrates, etc.).
• Synthesize observation and theory into quantitative models of various types in order to guide new experiments and theory.

Molecular Tracers of Contamination.

As part of the Stroud Center's 6-year NY Watersheds Project, the objectives the Molecular Tracers group are to identify the sources and assess the magnitude of contamination to the watersheds that feed NY City's drinking water supplies. At over 100 stream and river sites, we are analyzing the concentrations of 22 organic compounds. These include caffeine, laundry detergent fragrances and fecal steroids, which act as indicators of waste water treatment plant effluent, septic system failure and pathogens that may come from human, agricultural, and wildlife sources. We also measure polyaromatic hydrocarbons (PAHs), which are known, petroleum and combustion byproducts, to track urban and suburban runoff. The spatial and temporal patterns of these contaminants will eventually provide a tool to help guide limited resources toward management of these watershed. Collaborators: Bernard Sweeney, Charles Dow, Louis Kaplan, John Jackson, Tom Bott and Denis Newbold.

Carbon Dioxide Outgasing from Tropical Rivers.

We recently estimated that tropical rivers return about 1 gigaton per year of carbon as carbon dioxide to the atmosphere (Richey et al. Nature, 2002). This flux nearly rivals the amount of carbon released annually by deforestation, and as such our findings have received considerable press (see USA Today, WhyFiles, and University of Washington press release). Our latest results (Mayorga et al. Nature, 2005) show that this outgassing carbon dioxide is driven by respiration of terrestrial organic carbon that is less than five years old (see press release). We are currently conducting a broad survey of carbon dioxide concentrations in rivers of South America and South East Asia to better constrain the fluxes to the atmosphere and the ultimate sources of this carbon. Collaborators: Jeff Richey, Emilio Mayorga, Paul Quay, Alan Devol, Simone Alin (Univ. of Washington); Alex Krusche (CENA).

River Metabolism within the Amazon Basin.

Continuing work initiated during Post-Doctoral research, we are examining results and samples from river water incubation experiments in order to explore factors that control organic matter degradation dynamics as a function of its elemental and biochemical composition by size class. Multiple hypotheses have been suggested in the literature, but this is the first study to examine several controlling factors simultaneously. In addition, these field experiments have been designed to provide important constraints on parameterization of a new "River basin Organic Matter and Biogeochemistry Synthesis" model (ROMBUS) that I am currently developing in conjunction with the Carbon in the Amazon River Experiment (CAMREX) group at the University of Washington. Collaborators: Ronald Benner (Univ. South Carolina); Alex Krusche (CENA).

Radiocarbon Constraints on Organic Matter Turnover in the Amazon River Basin.

The objectives of this project are to: 1) Survey spatial and temporal variability in Δ 14C signatures of dissolved, fine particulate and course particulate organic carbon (DOC, FPOC and CPOC) and dissolved inorganic carbon (DIC) between basins of differing types and sizes; and to 2) Constrain age, turnover and pathways of these principal carbon fractions for the first phase of implementation and validation of a new "River basin Organic Matter and Biogeochemistry Synthesis" model (ROMBUS). Collaborators: Emilio Mayorga, John Hedges and Jeff Richey (Univ. of Washington); Carrie Massiello and Tom Brown (Center for Accelerator Mass Spectrometry).

Competition for Organic Molecules by Biodegradation and Sorption to Minerals.

In the environment, the composition natural organic matter is largely determined by its interactions with heterotrophic microorganisms and with mineral surfaces. Both biodegradation and sorption processes are highly selective — some molecules and molecular classes are degraded and sorbed in preference to others. The question thus arises as to what the interplay is between these two processes in determining organic matter composition, turnover and transport. Collaborators: John Hedges (

Aufdenkampe, A.K., D.B. Arscott, C.L. Dow, and L.J. Standley. 2006. Molecular tracers of soot and sewage contamination in streams supplying New York City drinking water. Journal of the North American Benthological Society 25:928-953. [ View PDF of article ; 457 KB]

Mayorga, E., A. K. Aufdenkampe, C. A. Masiello, A. V. Krusche, J. I. Hedges, P. D. Quay and J. E. Richey. 2005. Young organic matter as a source of carbon dioxide outgassing from Amazonian rivers. Nature 436(7050): 538-541. [ View PDF of article ; 325 KB | View PDF of Nature News & Views article by Raymond 2005 ; 449 KB]

Bernardes, M. C., L. A. Martinelli, A. V. Krusche, J. Gudeman, M. Moreira, R. L. Victoria, J. P. H. B. Ometto, M. V. R. Ballester, A. K. Aufdenkampe, et al. 2004. Riverine organic matter composition as a function of land use changes, southwest Amazon. Ecological Applications 14(4): S263-S279. [ View PDF of paper ; 1.7 MB]

Peterson, M. L., A. K. Aufdenkampe, S. Lang and J. I. Hedges. 2003. Dissolved organic carbon measurement using a modified high temperature DOC analyzer. Marine Chemistry, 81(1-2): 89 - 104. [ View PDF of paper ; 609 KB]

Mayorga, E. and A. K. Aufdenkampe. 2002. The processing of bioactive elements by the Amazon River system. The Ecohydrology of South American Rivers and Wetlands. M. E. McClain. Wallingford, UK, IAHS Press. IAHS Special Publication No. 6: 1-24. [ View PDF of paper ; 2.6 MB]

Richey, J. E., J. M. Melack, A. K. Aufdenkampe, V. M. Ballester and L. L. Hess. 2002. Outgassing from Amazonian rivers and wetlands as a large tropical source of atmospheric CO2. Nature, 416, 617-620. [ View PDF of paper ; 622 KB | View PDF of Nature News & Views, by Grace 2002 ; 126 KB]

Aufdenkampe, A. K. 2002. The Role of Sorptive Processes in the Organic Carbon and Nitrogen Cycles of the Amazon River Basin. Ph. D. Dissertation. University of Washington, School of Oceanography. Seattle. 164 pages.

Aufdenkampe, A. K., J. J. McCarthy, C. Navarette, M. Rodier, J. Dunne and J. W. Murray. 2002. Biogeochemical controls on new production in the tropical Pacific. Deep-Sea Research II, 49(13-14): 2619-2648. Equatorial Pacific Synthesis Special Issue. [ View PDF of paper ; 617 KB]

Aufdenkampe, A. K., and J. W. Murray. 2002. Controls on new production: The role of iron and physical processes. Deep-Sea Research II, 49(13-14): 2649-2668. Equatorial Pacific Synthesis Special Issue. [ View PDF of paper ; 476 KB]

Aufdenkampe, A. K., J. I. Hedges, A. V. Krusche, C. Llerena and J. E. Richey. 2001. Sorptive fractionation of dissolved organic nitrogen and amino acids onto sediments within the Amazon Basin. Limnology and Oceanography, 46(8), 1921-1935. [ View PDF of paper ; 224 KB]

Aufdenkampe, A. K., J. J. McCarthy, M. Rodier, C. Navarette, J. P. Dunne and J. W. Murray. 2001. Estimation of new production in the tropical Pacific. Global Biogeochemical Cycles, 15(1): 101-113. [ View PDF of paper ; 2428 KB]. [ View PDF of correction ; 223 KB]

Hedges, J. I., E. Mayorga, E. Tsamakis, M. E. McClain, A. K. Aufdenkampe, P. Quay, J. E. Richey, R. Benner, S. Opsahl, et al. 2000. Organic matter in Bolivian tributaries of the Amazon River: A comparison to the lower mainstem. Limnology and Oceanography 45(7): 1449-1466. [ View PDF of paper ; 320 KB]

Dunne, J. P., J. W. Murray, A. K. Aufdenkampe, S. Blain and M. Rodier. 1999. Silicon-nitrogen coupling in the equatorial Pacific upwelling zone. Global Biogeochemical Cycles 13(3): 715-726. [ View PDF of paper ; 4.1 MB

Supervisor

Michelle C. Cogo, M.S. student at Universidade de São Paulo, Brazil. Co-advisor, 2002-2005.
Angela Knapp, NASA OUR Earth Undergraduate Fellow at the University of Washington, 1998.

Reviewer

Biogeochemistry, Global Biogeochemical Cycles, Geochimica et Cosmochimica Acta, Journal of Environmental Quality, Journal of the North American Benthological Society, Limnology and Oceanography, Organic Geochemistry, Water Research..

Member

American Society of Limnology and Oceanography (ASLO); American Geophysical Union (AGU).

Guest Lecturer and Field Instructor

Taught lectures and week-long mini-units in:

• Introduction to Freshwater Ecology with T. Bott, University of Pennsylvania, 2004-2005.
• Introduction to Field Ecology with J. Thorne, University of Pennsylvania, 2003.
• Introductory Oceanography for C. Sarason, Seattle Central Community College, 2001
• Ocean Inquiry Project for C. Sarason, Seattle, 2001.
• River Basin Biogeochemistry for J. E. Richey and A. H. Devol, University of Washington, 2000.
• Biological Oceanography for J. Newton, Northeastern University (at Friday Harbor Labs), 1999.
• Introductory Oceanography for R. Carpenter, University of Washington, 1997.

Sustainable Agriculture Educator

U.S. Peace Corps, 1992-1994. Developed and implemented soil conservation programs and trained local extension agents. Central African Republic.

Languages

In order of proficiency: English, French, Portuguese, Sango (Central African Republic), Spanish.