Nitrogen Isotopes in Marine Sediments

The stable isotope composition of sedimentary organic matter has widely been used to describe the state of the oceanic nitrogen cycle as it allows conclusions on nitrogen sources and transformation processes (i.e. assimilation or denitrification), which are subject to isotopic fractionation (i.e. Francois et al. 1992 Altabet and Francois 1994 Altabet et al. 1999 Thunell et al. 2004). We will briefly discuss this issue because early diagenesis 

Deep water nitrate seems to have a fairly constant 8 N-level of about 5%o (Sigman et al. 

The Role of Oxygen, Nitrate and Phosphorus in Marine Sediments 

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