Mineralization
Mineralization of nitrogen follows that of carbon (see src/soil/littersum.c. First, for each soil layer the fluxes of carbon from the soil into the atmosphere is calculated and the respective fluxes of nitrogen go to the soil pools of nitrate and ammonia. Then the litter decomposition is calculated.
Fluxes (F) of carbon and nitrogen for slow (s) and fast (f) pools (P) depending on parameters ksoil10f=0.03 and ksoil10s=0.001 (per year) and the R(T) as a function of temperature (T) and soil moisture (M) per soil layer (l).
Whereas the fluxes for carbon go completely to the atmosphere, mineralized nitrogen is going to an intermediate ammonia pool in order to be available for Nitrification with different rates (after Parton et al. 2001.
Decomposition of organic material should be described in the main
documentation for litter.
The decomposition is as described in Sitch et al. 2003 and nitrogen
decomposition is linked into this. Here, the partition of the entire
decomposed material is described.
Carbon and nitrogen material that is to be decomposed (Decom for C and
N) is divided between the mineralized part (Af) and the part for
humification (1-Af).
The mineralized carbon goes to the atmosphere and the nitrogen goes to
an intermediate NH$4 pool.
The other part is divided between slow (s) and fast (f) carbon and
nitrogen soil pools (P) with parameter Ff for the portion that goes
to the fast soil pool.
Net mineralized material minerlitter, l is
which adds for nitrogen to the intermediate NH4 mineralization pool as well
A fraction of Knit=0.2 of this pool is nitrified directly per day to NO3 (see equation 2 in Parton et al. 2001 and the fluxes are added to the soil pools for ammonia and nitrate