TITLE: Pore water oxidant concentrations and reduction rates AUTHORS: Allan H. Devol University of Washington School of Oceanography Box 355351 Seattle, WA 98195 devol@u.washington.edu office: 206-549-1292 John P. Christensen Bigelow Laboratory for Ocean Sciences P.O. Box 475 180 McKown Point Road West Boothbay Harbor, ME 04575 jchristensen@bigelow.org office: 207-633-9601 FUNDING SOURCE AND GRANT NUMBER: NSF OPP0125275 DATA SET OVERVIEW: Contained within each of these files are the pore water concentrations of oxygen, nitrate+nitrite, ammonium, reduced manganese, and reduced iron for the summer 2002 SBI cruise (HLY0203) and the spring 2004 SBI cruise (HLY0402). Additionally included are diffusive flux derived sedimentary oxygen consumption rates, diffuse flux derived sedimentary denitrification rates, and sulfate reduction rates for both cruises. For spring 2004, additionally, there are oxygen consumption rates and denitrification rates calculated from whole core incubations. INSTRUMENT DESCRIPTION: Cores were collected using an Ocean Instruments Multicore 800. DATA COLLECTION and PROCESSING: Pore water oxygen concentrations were measured using a microelectrode. Pore water nitrate and ammonium concentrations were measured using methods from Grasshoff et al. (1999). Reduced iron and manganese concentrations were measured using atomic absorption spectroscopy. To measure oxygen and nitrogen gas concentrations in whole core incubations, two instruments were used: 1) a membrane inlet mass spectrometer (MIMS, Kana et al. 1994) and 2) Finnigan MAT 251 Isotope Ratio Mass Spectrometer (IRMS). Sulfate reduction rates were measured using the method by Jorgensen (1978). DATA FORMAT: Files names (Tab deliminated *.txt): Devol_HLY0203_porewaterO2.txt, Devol_HLY0203_porewaterNO3_NH4_Fe_Mn.txt, Devol_HLY0203_rates.txt, Devol_HLY0402_porewaterO2.txt, Devol_HLY0402_porewaterNO3_NH4_Fe_Mn.txt, Devol_HLY0402_rates.txt. All concentrations are in uM. All rates are in mmol/m2/d. Data that is missing or was not collected is recorded as "no data". REFERENCES: Grasshoff K, Kremling K, Ehrhardt M. (1999) _Methods of Seawater Analysis_ New York: Wiley. Jorgensen BB. (1978) Comparison of Methods for the Quantification of Bacterial Sulfate Reduction in Coastal Marine-Sediments .1. Measurement with Radiotracer Techniques. Geomicrobiology Journal 1: 11-27. Kana TM, Darkangelo C, Hunt MD, Oldham JB, Bennett GE, Cornwell JC. (1994) Membrane Inlet Mass-Spectrometer for Rapid High-Precision Determination of N-2, O-2, and Ar in Environmental Water Samples. Analytical Chemistry 66: 4166-4170.