Spatial coupling of nitrogen inputs and losses in the ocean

@article{Deutsch2007SpatialCO,
  title={Spatial coupling of nitrogen inputs and losses in the ocean},
  author={Curtis A. Deutsch and Jorge L. Sarmiento and Daniel M. Sigman and Nicolas Gruber and John P. Dunne},
  journal={Nature},
  year={2007},
  volume={445},
  pages={163-167}
}
Nitrogen fixation is crucial for maintaining biological productivity in the oceans, because it replaces the biologically available nitrogen that is lost through denitrification. But, owing to its temporal and spatial variability, the global distribution of marine nitrogen fixation is difficult to determine from direct shipboard measurements. This uncertainty limits our understanding of the factors that influence nitrogen fixation, which may include iron, nitrogen-to-phosphorus ratios, and… 
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