A balanced nitrogen budget of the surface layer of the southern Ross Sea, Antarctica

To understand marine biogeochemical cycles, it is critical to quantitatively balance organic matter transformations within the euphotic zone. Such an assessment for nitrogen is difficult because of lateral advection, uncertainties in individual measurements, the complexity of elemental transformatio...

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Bibliographic Details
Published in:Geophysical Research Letters
Main Author: Smith, Walker O., Jr.
Format: Text
Language:unknown
Published: W&M ScholarWorks 2000
Subjects:
Online Access:https://scholarworks.wm.edu/vimsarticles/1406
https://scholarworks.wm.edu/context/vimsarticles/article/2419/viewcontent/Smith_et_al_2000_Geophysical_Research_Letters.pdf
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Summary:To understand marine biogeochemical cycles, it is critical to quantitatively balance organic matter transformations within the euphotic zone. Such an assessment for nitrogen is difficult because of lateral advection, uncertainties in individual measurements, the complexity of elemental transformations (including nitrification and denitrification), and the difficulty of collecting data on appropriate space and time scales. Two cruises were conducted to the southern Ross Sea, Antarctica, to understand the time-varying fluxes of nitrogen into its various pools. From these data a balanced inventory was constructed. Nitrate removal in the upper 200 m was balanced by particulate and dissolved organic nitrogen production, ammonification, and vertical flux. In austral spring nearly all (92%) of the new production remained as particulate nitrogen, but this percentage decreased markedly (52%) by mid-summer, when nitrogen regeneration, PN flux, and DON production were 23, 13 and 12% of net production, respectively. The organic matter budget in this coastal Antarctic site is dominated by particle transformations.