FY 2010 Temporary uncoupling of the marine nitrogen cycle: Accumulation of nitrite on the Bering Sea Shelf Mordy, C.W., L. Eisner, P. Proctor, P.J. Stabeno, A. Devol, D.H. Shull, J.M. Napp, and T. Whitledge Mar. Chem., 121, 157–166, doi: 10.1016/j.marchem.2010.04.004 (2010) An unprecedented pool of nitrite (2–5.6 µM) was observed in the well-oxygenated, ammonium-rich bottom waters of Bering Sea middle shelf in fall 2005 on two simultaneous oceanographic cruises. This nitrite pool was located in a transition zone that separated the ice-derived cold pool to the north from warmer waters to the south. The transition zone was influenced by on-shelf flow. The nitrite pool was transitory; it was not apparent 11 days after it was first observed. Several origins of the pool were considered including: truncation of sedimentary denitrification and/or curtailment of anammox (these are dominate pathways in the nitrogen cycle of the Bering Sea), nitrite release from light-limited phytoplankton (light and nutrient conditions were favorable for this mechanism), and truncation of water column nitrification (there was a small decrease of ammonium in the vicinity of the nitrite pool). The occurrence of this pool suggests a temporary uncoupling of the marine nitrogen cycle. Feature Publications | Outstanding Scientific Publications Contact Sandra Bigley | Help
