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Read Full Article (file size: 105734 bytes) Cited by
GEOPHYSICAL RESEARCH LETTERS,
VOL. 32,
L13817,
doi:10.1029/2004GL022121,
2005
Isotopic composition of Antarctic Dry Valley nitrate: Implications for NOy sources and cycling in Antarctica
G. Michalski
Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana, USA Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, USA
J. G. Bockheim
Department of Soil Science, University of Wisconsin-Madison, Madison, Wisconsin, USA
C. Kendall
United States Geological Survey, Menlo Park, California, USA
M. Thiemens
Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, USA
Abstract
Nitrates minerals from the Dry Valleys of Antarctica have been analyzed for their oxygen and nitrogen isotopic compositions.
The 15N was depleted with δ15N values ranging from −9.5 to −26.2‰, whereas the 17O and 18O isotopes were highly enriched (with excess 17O) with δ18O values spanning 62–76‰ and Δ17O values from 28.9 to 32.7‰. These are the largest 17O enrichments observed in any known mineral. The oxygen isotopes indicate that nitrate is from a combination of tropospheric
transport of photochemically produced HNO3 and HNO3 formed in the stratosphere.
Received 30
November
2004;
accepted 19
May
2005;
published 9
July
2005.
Index Terms: 0426 Biogeosciences: Biosphere/atmosphere interactions (0315); 0444 Biogeosciences: Evolutionary geobiology; 0469 Biogeosciences: Nitrogen cycling; 0486 Biogeosciences: Soils/pedology (1865); 0793 Cryosphere: Biogeochemistry (0412, 0414, 1615, 4805, 4912).
Read Full Article (file size: 105734 bytes) Cited by
Citation: Michalski, G., J. G. Bockheim, C. Kendall, and M. Thiemens
(2005),
Isotopic composition of Antarctic Dry Valley nitrate: Implications for NOy sources and cycling in Antarctica,
Geophys. Res. Lett.,
32,
L13817,
doi:10.1029/2004GL022121.
Copyright 2005 by the American Geophysical Union.
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